Do I have a twin with permutated remainders?












17












$begingroup$


We define $R_n$ as the list of remainders of the Euclidean division of $n$ by $2$, $3$, $5$ and $7$.



Given an integer $nge0$, you have to figure out if there exists an integer $0<k<210$ such that $R_{n+k}$ is a permutation of $R_n$.



Examples



The criterion is met for $n=8$, because:




  • we have $R_8=(0,2,3,1)$

  • for $k=44$, we have $R_{n+k}=R_{52}=(0,1,2,3)$, which is a permutation of $R_8$


The criterion is not met for $n=48$, because:




  • we have $R_{48}=(0,0,3,6)$

  • the smallest integer $k>0$ such that $R_{n+k}$ is a permutation of $R_{48}$ is $k=210$ (leading to $R_{258}=(0,0,3,6)$ as well)


Rules




  • You may either output a truthy value if $k$ exists and a falsy value otherwise, or two distinct and consistent values of your choice.

  • This is code-golf.


Hint




Do you really need to compute $k$? Well, maybe. Or maybe not.




Test cases



Some values of $n$ for which $k$ exists:



3, 4, 5, 8, 30, 100, 200, 2019


Some values of $n$ for which $k$ does not exist:



0, 1, 2, 13, 19, 48, 210, 1999









share|improve this question









$endgroup$

















    17












    $begingroup$


    We define $R_n$ as the list of remainders of the Euclidean division of $n$ by $2$, $3$, $5$ and $7$.



    Given an integer $nge0$, you have to figure out if there exists an integer $0<k<210$ such that $R_{n+k}$ is a permutation of $R_n$.



    Examples



    The criterion is met for $n=8$, because:




    • we have $R_8=(0,2,3,1)$

    • for $k=44$, we have $R_{n+k}=R_{52}=(0,1,2,3)$, which is a permutation of $R_8$


    The criterion is not met for $n=48$, because:




    • we have $R_{48}=(0,0,3,6)$

    • the smallest integer $k>0$ such that $R_{n+k}$ is a permutation of $R_{48}$ is $k=210$ (leading to $R_{258}=(0,0,3,6)$ as well)


    Rules




    • You may either output a truthy value if $k$ exists and a falsy value otherwise, or two distinct and consistent values of your choice.

    • This is code-golf.


    Hint




    Do you really need to compute $k$? Well, maybe. Or maybe not.




    Test cases



    Some values of $n$ for which $k$ exists:



    3, 4, 5, 8, 30, 100, 200, 2019


    Some values of $n$ for which $k$ does not exist:



    0, 1, 2, 13, 19, 48, 210, 1999









    share|improve this question









    $endgroup$















      17












      17








      17





      $begingroup$


      We define $R_n$ as the list of remainders of the Euclidean division of $n$ by $2$, $3$, $5$ and $7$.



      Given an integer $nge0$, you have to figure out if there exists an integer $0<k<210$ such that $R_{n+k}$ is a permutation of $R_n$.



      Examples



      The criterion is met for $n=8$, because:




      • we have $R_8=(0,2,3,1)$

      • for $k=44$, we have $R_{n+k}=R_{52}=(0,1,2,3)$, which is a permutation of $R_8$


      The criterion is not met for $n=48$, because:




      • we have $R_{48}=(0,0,3,6)$

      • the smallest integer $k>0$ such that $R_{n+k}$ is a permutation of $R_{48}$ is $k=210$ (leading to $R_{258}=(0,0,3,6)$ as well)


      Rules




      • You may either output a truthy value if $k$ exists and a falsy value otherwise, or two distinct and consistent values of your choice.

      • This is code-golf.


      Hint




      Do you really need to compute $k$? Well, maybe. Or maybe not.




      Test cases



      Some values of $n$ for which $k$ exists:



      3, 4, 5, 8, 30, 100, 200, 2019


      Some values of $n$ for which $k$ does not exist:



      0, 1, 2, 13, 19, 48, 210, 1999









      share|improve this question









      $endgroup$




      We define $R_n$ as the list of remainders of the Euclidean division of $n$ by $2$, $3$, $5$ and $7$.



      Given an integer $nge0$, you have to figure out if there exists an integer $0<k<210$ such that $R_{n+k}$ is a permutation of $R_n$.



      Examples



      The criterion is met for $n=8$, because:




      • we have $R_8=(0,2,3,1)$

      • for $k=44$, we have $R_{n+k}=R_{52}=(0,1,2,3)$, which is a permutation of $R_8$


      The criterion is not met for $n=48$, because:




      • we have $R_{48}=(0,0,3,6)$

      • the smallest integer $k>0$ such that $R_{n+k}$ is a permutation of $R_{48}$ is $k=210$ (leading to $R_{258}=(0,0,3,6)$ as well)


      Rules




      • You may either output a truthy value if $k$ exists and a falsy value otherwise, or two distinct and consistent values of your choice.

      • This is code-golf.


      Hint




      Do you really need to compute $k$? Well, maybe. Or maybe not.




      Test cases



      Some values of $n$ for which $k$ exists:



      3, 4, 5, 8, 30, 100, 200, 2019


      Some values of $n$ for which $k$ does not exist:



      0, 1, 2, 13, 19, 48, 210, 1999






      code-golf decision-problem number-theory






      share|improve this question













      share|improve this question











      share|improve this question




      share|improve this question










      asked Apr 4 at 15:36









      ArnauldArnauld

      81.7k797336




      81.7k797336






















          16 Answers
          16






          active

          oldest

          votes


















          20












          $begingroup$


          R, 63 59 bytes





          s=scan()%%c(2,3,5,7);i=which(s<c(0,2,3,5));any(s[i]-s[i-1])


          Try it online!



          -4 bytes thanks to Giuseppe



          (The explanation contains a spoiler as to how to solve the problem without computing $k$.)



          Explanation:
          Let $s$ be the list of remainders. Note the constraint that s[1]<2, s[2]<3, s[3]<5 and s[4]<7. By the Chinese Remainder Theorem, there exists a $k$ iff there is a permutation of $s$, distinct from $s$, which verifies the constraint. In practice, this will be verified if one of the following conditions is verified:




          • s[2]<2 and s[2]!=s[1]

          • s[3]<3 and s[3]!=s[2]

          • s[4]<5 and s[4]!=s[3]


          The code can probably be golfed further.






          share|improve this answer











          $endgroup$













          • $begingroup$
            Could you explain why the permutation is necessarily distinct from $s$?
            $endgroup$
            – dfeuer
            Apr 5 at 18:41








          • 1




            $begingroup$
            @dfeuer It is a consequence of the Chinese Remainder Theorem; I added a link. If two integers have the same remainders modulo 2, 3, 5 and 7 (without a permutation), then the two integers are equal modulo 2*3*5*7=210.
            $endgroup$
            – Robin Ryder
            Apr 5 at 19:46



















          8












          $begingroup$


          Haskell, 69 bytes



          Based on the Chinese remainder theorem





          m=[2,3,5,7]
          f x|s<-mod x<$>m=or[m!!a>b|a<-[0..2],b<-drop a s,s!!a/=b]


          Try it online!






          share|improve this answer









          $endgroup$









          • 4




            $begingroup$
            Actually, my working title for this challenge was "Do I have a Chinese twin?" :)
            $endgroup$
            – Arnauld
            Apr 5 at 10:22



















          5












          $begingroup$


          Perl 6, 64 61 59 43 bytes





          {map($!=(*X%2,3,5,7).Bag,^209+$_+1)∋.&$!}


          Try it online!



          -16 thanks to @Jo King






          share|improve this answer











          $endgroup$





















            4












            $begingroup$


            Python 2, 41 bytes





            lambda n:n%5!=n%7<5or n%3!=n%5<3or-~n%6/4


            Try it online!



            Uses the same characterization as Robin Ryder. The check n%2!=n%3<2 is shortened to -~n%6/4. Writing out the three conditions turned out shorter than writing a general one:



            46 bytes





            lambda n:any(n%p!=n%(p+1|1)<p for p in[2,3,5])


            Try it online!






            share|improve this answer











            $endgroup$





















              4












              $begingroup$


              Haskell, 47 bytes





              g.mod
              g r|let p?q=r p/=r q&&r q<p=2?3||3?5||5?7


              Try it online!






              share|improve this answer











              $endgroup$













              • $begingroup$
                Can you explain?
                $endgroup$
                – dfeuer
                Apr 5 at 6:24






              • 1




                $begingroup$
                @dfeuer It's using Robin Ryder's method.
                $endgroup$
                – Ørjan Johansen
                Apr 5 at 17:39



















              4












              $begingroup$


              C# (Visual C# Interactive Compiler), 125 42 38 36 bytes





              n=>n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


              Direct port of @xnor's answer, which is based off of @RobinRyder's solution.



              Saved 4 bytes thanks to @Ørjan Johansen!



              Saved 2 more thanks to @Arnauld!



              Try it online!






              share|improve this answer











              $endgroup$









              • 1




                $begingroup$
                I found a variation that only ties for xnor's languages but helps for this: 38 bytes
                $endgroup$
                – Ørjan Johansen
                Apr 5 at 6:04






              • 1




                $begingroup$
                Isn't -~n%6/4>0 just -~n%6>3?
                $endgroup$
                – Arnauld
                Apr 6 at 9:55










              • $begingroup$
                BTW, this is a JavaScript polyglot.
                $endgroup$
                – Arnauld
                Apr 7 at 7:55



















              3












              $begingroup$


              Wolfram Language (Mathematica), 67 bytes



              !FreeQ[Sort/@Table[R[#+k],{k,209}],Sort@R@#]&
              R@n_:=n~Mod~{2,3,5,7}


              Try it online!






              share|improve this answer











              $endgroup$





















                2












                $begingroup$


                Ruby, 54 bytes





                ->n{[2,3,5,7].each_cons(2).any?{|l,h|n%l!=n%h&&n%h<l}}


                Try it online!



                Uses Robin Ryder's clever solution.






                share|improve this answer









                $endgroup$





















                  2












                  $begingroup$


                  Java (JDK), 36 bytes





                  n->n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                  Try it online!



                  Credits




                  • Port of xnor's solution, improved by Ørjan Johansen.






                  share|improve this answer











                  $endgroup$





















                    1












                    $begingroup$


                    R, 72 bytes





                    n=scan();b=c(2,3,5,7);for(i in n+1:209)F=F|all(sort(n%%b)==sort(i%%b));F


                    Try it online!






                    share|improve this answer









                    $endgroup$





















                      1












                      $begingroup$


                      PHP, 81 78 72 bytes





                      while($y<3)if($argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u)die(T);


                      A riff on @Robin Ryder's answer. Input is via STDIN, output is 'T' if truthy, and empty '' if falsy.



                      $ echo 3|php -nF euc.php
                      T
                      $ echo 5|php -nF euc.php
                      T
                      $ echo 2019|php -nF euc.php
                      T
                      $ echo 0|php -nF euc.php

                      $ echo 2|php -nF euc.php

                      $ echo 1999|php -nF euc.php


                      Try it online!



                      Or 73 bytes with 1 or 0 response



                      while($y<3)$r|=$argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u;echo$r;



                      $ echo 2019|php -nF euc.php
                      1
                      $ echo 1999|php -nF euc.php
                      0


                      Try it online (all test cases)!



                      Original answer, 133 127 bytes



                      function($n){while(++$k<210)if(($r=function($n){foreach([2,3,5,7]as$d)$o=$n%$d;sort($o);return$o;})($n+$k)==$r($n))return 1;}


                      Try it online!






                      share|improve this answer











                      $endgroup$





















                        1












                        $begingroup$


                        Python 3, 69 bytes





                        lambda x:int('4LR2991ODO5GS2974QWH22YTLL3E3I6TDADQG87I0',36)&1<<x%210


                        Try it online!



                        Hardcoded






                        share|improve this answer









                        $endgroup$





















                          1












                          $begingroup$


                          05AB1E, 16 bytes



                          Ƶ.L+ε‚ε4Åp%{}Ë}à


                          Try it online or verify all test cases.



                          Explanation:





                          Ƶ.L          # Create a list in the range [1,209] (which is k)
                          + # Add the (implicit) input to each (which is n+k)
                          ε # Map each value to:
                          ‚ # Pair it with the (implicit) input
                          ε # Map both to:
                          4Åp # Get the first 4 primes: [2,3,5,7]
                          % # Modulo the current number by each of these four (now we have R_n and R_n+k)
                          { # Sort the list
                          }Ë # After the inner map: check if both sorted lists are equal
                          }à # After the outer map: check if any are truthy by taking the maximum
                          # (which is output implicitly as result)


                          See this 05AB1E tip of mine (section How to compress large integers?) to understand why Ƶ. is 209.






                          share|improve this answer









                          $endgroup$





















                            1












                            $begingroup$


                            J, 40 bytes



                            1 e.(>:+i.@209)-:&(/:~)&(2 3 5 7&|"1 0)]


                            Try it online!



                            Brute force...






                            share|improve this answer









                            $endgroup$





















                              1












                              $begingroup$


                              Wolfram Language (Mathematica), 56 bytes



                              Or@@(Min[s-#]>0&/@Rest@Permutations@Mod[#,s={2,3,5,7}])&


                              Try it online!



                              Finds all non-identity permutations of the remainders of the input modulo 2, 3, 5, 7, and checks if any of them are below {2,3,5,7} in each coordinate. Note that Or@@{} is False.






                              share|improve this answer









                              $endgroup$





















                                1












                                $begingroup$


                                Jelly, 15 bytes



                                8ÆR©PḶ+%Ṣ¥€®ċḢ$


                                Try it online!



                                I’m sure there’s a golfier answer. I’ve interpreted a truthy value as being anything that isn’t zero, so here it’s the number of possible values of k. If it needs to be two distinct values that costs me a further byte.



                                Explanation



                                8ÆR             | Primes less than 8 [2,3,5,7]
                                © | Copy to register
                                P | Product [210]
                                Ḷ | Lowered range [0, 1, ..., 208, 209]
                                + | Add to input
                                ¥€ | For each of these 210 numbers...
                                % ® | Modulo 2, 3, 5, 7
                                Ṣ | And sort
                                ċḢ$ | Count how many match the first (input) number’s remainders





                                share|improve this answer











                                $endgroup$









                                • 1




                                  $begingroup$
                                  All good regarding truthy vs falsey. Using the meta agreed definition of truthy and falsey (effectively "what does the language's if-else construct do if there is one) zero is falsey and non-zeros are truthy (? is the if-else construct in Jelly; for some languages it's a harder question).
                                  $endgroup$
                                  – Jonathan Allan
                                  Apr 4 at 18:08










                                • $begingroup$
                                  Oh, and you could get distinct values for no cost with Ḣe$ if you wanted :)
                                  $endgroup$
                                  – Jonathan Allan
                                  Apr 4 at 18:11










                                • $begingroup$
                                  @JonathanAllan yes of course, thanks. :)
                                  $endgroup$
                                  – Nick Kennedy
                                  Apr 4 at 18:12














                                Your Answer






                                StackExchange.ifUsing("editor", function () {
                                StackExchange.using("externalEditor", function () {
                                StackExchange.using("snippets", function () {
                                StackExchange.snippets.init();
                                });
                                });
                                }, "code-snippets");

                                StackExchange.ready(function() {
                                var channelOptions = {
                                tags: "".split(" "),
                                id: "200"
                                };
                                initTagRenderer("".split(" "), "".split(" "), channelOptions);

                                StackExchange.using("externalEditor", function() {
                                // Have to fire editor after snippets, if snippets enabled
                                if (StackExchange.settings.snippets.snippetsEnabled) {
                                StackExchange.using("snippets", function() {
                                createEditor();
                                });
                                }
                                else {
                                createEditor();
                                }
                                });

                                function createEditor() {
                                StackExchange.prepareEditor({
                                heartbeatType: 'answer',
                                autoActivateHeartbeat: false,
                                convertImagesToLinks: false,
                                noModals: true,
                                showLowRepImageUploadWarning: true,
                                reputationToPostImages: null,
                                bindNavPrevention: true,
                                postfix: "",
                                imageUploader: {
                                brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
                                contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
                                allowUrls: true
                                },
                                onDemand: true,
                                discardSelector: ".discard-answer"
                                ,immediatelyShowMarkdownHelp:true
                                });


                                }
                                });














                                draft saved

                                draft discarded


















                                StackExchange.ready(
                                function () {
                                StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcodegolf.stackexchange.com%2fquestions%2f182669%2fdo-i-have-a-twin-with-permutated-remainders%23new-answer', 'question_page');
                                }
                                );

                                Post as a guest















                                Required, but never shown

























                                16 Answers
                                16






                                active

                                oldest

                                votes








                                16 Answers
                                16






                                active

                                oldest

                                votes









                                active

                                oldest

                                votes






                                active

                                oldest

                                votes









                                20












                                $begingroup$


                                R, 63 59 bytes





                                s=scan()%%c(2,3,5,7);i=which(s<c(0,2,3,5));any(s[i]-s[i-1])


                                Try it online!



                                -4 bytes thanks to Giuseppe



                                (The explanation contains a spoiler as to how to solve the problem without computing $k$.)



                                Explanation:
                                Let $s$ be the list of remainders. Note the constraint that s[1]<2, s[2]<3, s[3]<5 and s[4]<7. By the Chinese Remainder Theorem, there exists a $k$ iff there is a permutation of $s$, distinct from $s$, which verifies the constraint. In practice, this will be verified if one of the following conditions is verified:




                                • s[2]<2 and s[2]!=s[1]

                                • s[3]<3 and s[3]!=s[2]

                                • s[4]<5 and s[4]!=s[3]


                                The code can probably be golfed further.






                                share|improve this answer











                                $endgroup$













                                • $begingroup$
                                  Could you explain why the permutation is necessarily distinct from $s$?
                                  $endgroup$
                                  – dfeuer
                                  Apr 5 at 18:41








                                • 1




                                  $begingroup$
                                  @dfeuer It is a consequence of the Chinese Remainder Theorem; I added a link. If two integers have the same remainders modulo 2, 3, 5 and 7 (without a permutation), then the two integers are equal modulo 2*3*5*7=210.
                                  $endgroup$
                                  – Robin Ryder
                                  Apr 5 at 19:46
















                                20












                                $begingroup$


                                R, 63 59 bytes





                                s=scan()%%c(2,3,5,7);i=which(s<c(0,2,3,5));any(s[i]-s[i-1])


                                Try it online!



                                -4 bytes thanks to Giuseppe



                                (The explanation contains a spoiler as to how to solve the problem without computing $k$.)



                                Explanation:
                                Let $s$ be the list of remainders. Note the constraint that s[1]<2, s[2]<3, s[3]<5 and s[4]<7. By the Chinese Remainder Theorem, there exists a $k$ iff there is a permutation of $s$, distinct from $s$, which verifies the constraint. In practice, this will be verified if one of the following conditions is verified:




                                • s[2]<2 and s[2]!=s[1]

                                • s[3]<3 and s[3]!=s[2]

                                • s[4]<5 and s[4]!=s[3]


                                The code can probably be golfed further.






                                share|improve this answer











                                $endgroup$













                                • $begingroup$
                                  Could you explain why the permutation is necessarily distinct from $s$?
                                  $endgroup$
                                  – dfeuer
                                  Apr 5 at 18:41








                                • 1




                                  $begingroup$
                                  @dfeuer It is a consequence of the Chinese Remainder Theorem; I added a link. If two integers have the same remainders modulo 2, 3, 5 and 7 (without a permutation), then the two integers are equal modulo 2*3*5*7=210.
                                  $endgroup$
                                  – Robin Ryder
                                  Apr 5 at 19:46














                                20












                                20








                                20





                                $begingroup$


                                R, 63 59 bytes





                                s=scan()%%c(2,3,5,7);i=which(s<c(0,2,3,5));any(s[i]-s[i-1])


                                Try it online!



                                -4 bytes thanks to Giuseppe



                                (The explanation contains a spoiler as to how to solve the problem without computing $k$.)



                                Explanation:
                                Let $s$ be the list of remainders. Note the constraint that s[1]<2, s[2]<3, s[3]<5 and s[4]<7. By the Chinese Remainder Theorem, there exists a $k$ iff there is a permutation of $s$, distinct from $s$, which verifies the constraint. In practice, this will be verified if one of the following conditions is verified:




                                • s[2]<2 and s[2]!=s[1]

                                • s[3]<3 and s[3]!=s[2]

                                • s[4]<5 and s[4]!=s[3]


                                The code can probably be golfed further.






                                share|improve this answer











                                $endgroup$




                                R, 63 59 bytes





                                s=scan()%%c(2,3,5,7);i=which(s<c(0,2,3,5));any(s[i]-s[i-1])


                                Try it online!



                                -4 bytes thanks to Giuseppe



                                (The explanation contains a spoiler as to how to solve the problem without computing $k$.)



                                Explanation:
                                Let $s$ be the list of remainders. Note the constraint that s[1]<2, s[2]<3, s[3]<5 and s[4]<7. By the Chinese Remainder Theorem, there exists a $k$ iff there is a permutation of $s$, distinct from $s$, which verifies the constraint. In practice, this will be verified if one of the following conditions is verified:




                                • s[2]<2 and s[2]!=s[1]

                                • s[3]<3 and s[3]!=s[2]

                                • s[4]<5 and s[4]!=s[3]


                                The code can probably be golfed further.







                                share|improve this answer














                                share|improve this answer



                                share|improve this answer








                                edited Apr 6 at 8:02

























                                answered Apr 4 at 17:00









                                Robin RyderRobin Ryder

                                85112




                                85112












                                • $begingroup$
                                  Could you explain why the permutation is necessarily distinct from $s$?
                                  $endgroup$
                                  – dfeuer
                                  Apr 5 at 18:41








                                • 1




                                  $begingroup$
                                  @dfeuer It is a consequence of the Chinese Remainder Theorem; I added a link. If two integers have the same remainders modulo 2, 3, 5 and 7 (without a permutation), then the two integers are equal modulo 2*3*5*7=210.
                                  $endgroup$
                                  – Robin Ryder
                                  Apr 5 at 19:46


















                                • $begingroup$
                                  Could you explain why the permutation is necessarily distinct from $s$?
                                  $endgroup$
                                  – dfeuer
                                  Apr 5 at 18:41








                                • 1




                                  $begingroup$
                                  @dfeuer It is a consequence of the Chinese Remainder Theorem; I added a link. If two integers have the same remainders modulo 2, 3, 5 and 7 (without a permutation), then the two integers are equal modulo 2*3*5*7=210.
                                  $endgroup$
                                  – Robin Ryder
                                  Apr 5 at 19:46
















                                $begingroup$
                                Could you explain why the permutation is necessarily distinct from $s$?
                                $endgroup$
                                – dfeuer
                                Apr 5 at 18:41






                                $begingroup$
                                Could you explain why the permutation is necessarily distinct from $s$?
                                $endgroup$
                                – dfeuer
                                Apr 5 at 18:41






                                1




                                1




                                $begingroup$
                                @dfeuer It is a consequence of the Chinese Remainder Theorem; I added a link. If two integers have the same remainders modulo 2, 3, 5 and 7 (without a permutation), then the two integers are equal modulo 2*3*5*7=210.
                                $endgroup$
                                – Robin Ryder
                                Apr 5 at 19:46




                                $begingroup$
                                @dfeuer It is a consequence of the Chinese Remainder Theorem; I added a link. If two integers have the same remainders modulo 2, 3, 5 and 7 (without a permutation), then the two integers are equal modulo 2*3*5*7=210.
                                $endgroup$
                                – Robin Ryder
                                Apr 5 at 19:46











                                8












                                $begingroup$


                                Haskell, 69 bytes



                                Based on the Chinese remainder theorem





                                m=[2,3,5,7]
                                f x|s<-mod x<$>m=or[m!!a>b|a<-[0..2],b<-drop a s,s!!a/=b]


                                Try it online!






                                share|improve this answer









                                $endgroup$









                                • 4




                                  $begingroup$
                                  Actually, my working title for this challenge was "Do I have a Chinese twin?" :)
                                  $endgroup$
                                  – Arnauld
                                  Apr 5 at 10:22
















                                8












                                $begingroup$


                                Haskell, 69 bytes



                                Based on the Chinese remainder theorem





                                m=[2,3,5,7]
                                f x|s<-mod x<$>m=or[m!!a>b|a<-[0..2],b<-drop a s,s!!a/=b]


                                Try it online!






                                share|improve this answer









                                $endgroup$









                                • 4




                                  $begingroup$
                                  Actually, my working title for this challenge was "Do I have a Chinese twin?" :)
                                  $endgroup$
                                  – Arnauld
                                  Apr 5 at 10:22














                                8












                                8








                                8





                                $begingroup$


                                Haskell, 69 bytes



                                Based on the Chinese remainder theorem





                                m=[2,3,5,7]
                                f x|s<-mod x<$>m=or[m!!a>b|a<-[0..2],b<-drop a s,s!!a/=b]


                                Try it online!






                                share|improve this answer









                                $endgroup$




                                Haskell, 69 bytes



                                Based on the Chinese remainder theorem





                                m=[2,3,5,7]
                                f x|s<-mod x<$>m=or[m!!a>b|a<-[0..2],b<-drop a s,s!!a/=b]


                                Try it online!







                                share|improve this answer












                                share|improve this answer



                                share|improve this answer










                                answered Apr 4 at 16:45









                                H.PWizH.PWiz

                                10.4k21353




                                10.4k21353








                                • 4




                                  $begingroup$
                                  Actually, my working title for this challenge was "Do I have a Chinese twin?" :)
                                  $endgroup$
                                  – Arnauld
                                  Apr 5 at 10:22














                                • 4




                                  $begingroup$
                                  Actually, my working title for this challenge was "Do I have a Chinese twin?" :)
                                  $endgroup$
                                  – Arnauld
                                  Apr 5 at 10:22








                                4




                                4




                                $begingroup$
                                Actually, my working title for this challenge was "Do I have a Chinese twin?" :)
                                $endgroup$
                                – Arnauld
                                Apr 5 at 10:22




                                $begingroup$
                                Actually, my working title for this challenge was "Do I have a Chinese twin?" :)
                                $endgroup$
                                – Arnauld
                                Apr 5 at 10:22











                                5












                                $begingroup$


                                Perl 6, 64 61 59 43 bytes





                                {map($!=(*X%2,3,5,7).Bag,^209+$_+1)∋.&$!}


                                Try it online!



                                -16 thanks to @Jo King






                                share|improve this answer











                                $endgroup$


















                                  5












                                  $begingroup$


                                  Perl 6, 64 61 59 43 bytes





                                  {map($!=(*X%2,3,5,7).Bag,^209+$_+1)∋.&$!}


                                  Try it online!



                                  -16 thanks to @Jo King






                                  share|improve this answer











                                  $endgroup$
















                                    5












                                    5








                                    5





                                    $begingroup$


                                    Perl 6, 64 61 59 43 bytes





                                    {map($!=(*X%2,3,5,7).Bag,^209+$_+1)∋.&$!}


                                    Try it online!



                                    -16 thanks to @Jo King






                                    share|improve this answer











                                    $endgroup$




                                    Perl 6, 64 61 59 43 bytes





                                    {map($!=(*X%2,3,5,7).Bag,^209+$_+1)∋.&$!}


                                    Try it online!



                                    -16 thanks to @Jo King







                                    share|improve this answer














                                    share|improve this answer



                                    share|improve this answer








                                    edited Apr 5 at 8:09

























                                    answered Apr 4 at 16:20









                                    VenVen

                                    2,89011223




                                    2,89011223























                                        4












                                        $begingroup$


                                        Python 2, 41 bytes





                                        lambda n:n%5!=n%7<5or n%3!=n%5<3or-~n%6/4


                                        Try it online!



                                        Uses the same characterization as Robin Ryder. The check n%2!=n%3<2 is shortened to -~n%6/4. Writing out the three conditions turned out shorter than writing a general one:



                                        46 bytes





                                        lambda n:any(n%p!=n%(p+1|1)<p for p in[2,3,5])


                                        Try it online!






                                        share|improve this answer











                                        $endgroup$


















                                          4












                                          $begingroup$


                                          Python 2, 41 bytes





                                          lambda n:n%5!=n%7<5or n%3!=n%5<3or-~n%6/4


                                          Try it online!



                                          Uses the same characterization as Robin Ryder. The check n%2!=n%3<2 is shortened to -~n%6/4. Writing out the three conditions turned out shorter than writing a general one:



                                          46 bytes





                                          lambda n:any(n%p!=n%(p+1|1)<p for p in[2,3,5])


                                          Try it online!






                                          share|improve this answer











                                          $endgroup$
















                                            4












                                            4








                                            4





                                            $begingroup$


                                            Python 2, 41 bytes





                                            lambda n:n%5!=n%7<5or n%3!=n%5<3or-~n%6/4


                                            Try it online!



                                            Uses the same characterization as Robin Ryder. The check n%2!=n%3<2 is shortened to -~n%6/4. Writing out the three conditions turned out shorter than writing a general one:



                                            46 bytes





                                            lambda n:any(n%p!=n%(p+1|1)<p for p in[2,3,5])


                                            Try it online!






                                            share|improve this answer











                                            $endgroup$




                                            Python 2, 41 bytes





                                            lambda n:n%5!=n%7<5or n%3!=n%5<3or-~n%6/4


                                            Try it online!



                                            Uses the same characterization as Robin Ryder. The check n%2!=n%3<2 is shortened to -~n%6/4. Writing out the three conditions turned out shorter than writing a general one:



                                            46 bytes





                                            lambda n:any(n%p!=n%(p+1|1)<p for p in[2,3,5])


                                            Try it online!







                                            share|improve this answer














                                            share|improve this answer



                                            share|improve this answer








                                            edited Apr 5 at 4:16

























                                            answered Apr 5 at 0:34









                                            xnorxnor

                                            94.3k18192452




                                            94.3k18192452























                                                4












                                                $begingroup$


                                                Haskell, 47 bytes





                                                g.mod
                                                g r|let p?q=r p/=r q&&r q<p=2?3||3?5||5?7


                                                Try it online!






                                                share|improve this answer











                                                $endgroup$













                                                • $begingroup$
                                                  Can you explain?
                                                  $endgroup$
                                                  – dfeuer
                                                  Apr 5 at 6:24






                                                • 1




                                                  $begingroup$
                                                  @dfeuer It's using Robin Ryder's method.
                                                  $endgroup$
                                                  – Ørjan Johansen
                                                  Apr 5 at 17:39
















                                                4












                                                $begingroup$


                                                Haskell, 47 bytes





                                                g.mod
                                                g r|let p?q=r p/=r q&&r q<p=2?3||3?5||5?7


                                                Try it online!






                                                share|improve this answer











                                                $endgroup$













                                                • $begingroup$
                                                  Can you explain?
                                                  $endgroup$
                                                  – dfeuer
                                                  Apr 5 at 6:24






                                                • 1




                                                  $begingroup$
                                                  @dfeuer It's using Robin Ryder's method.
                                                  $endgroup$
                                                  – Ørjan Johansen
                                                  Apr 5 at 17:39














                                                4












                                                4








                                                4





                                                $begingroup$


                                                Haskell, 47 bytes





                                                g.mod
                                                g r|let p?q=r p/=r q&&r q<p=2?3||3?5||5?7


                                                Try it online!






                                                share|improve this answer











                                                $endgroup$




                                                Haskell, 47 bytes





                                                g.mod
                                                g r|let p?q=r p/=r q&&r q<p=2?3||3?5||5?7


                                                Try it online!







                                                share|improve this answer














                                                share|improve this answer



                                                share|improve this answer








                                                edited Apr 5 at 5:27

























                                                answered Apr 5 at 5:19









                                                xnorxnor

                                                94.3k18192452




                                                94.3k18192452












                                                • $begingroup$
                                                  Can you explain?
                                                  $endgroup$
                                                  – dfeuer
                                                  Apr 5 at 6:24






                                                • 1




                                                  $begingroup$
                                                  @dfeuer It's using Robin Ryder's method.
                                                  $endgroup$
                                                  – Ørjan Johansen
                                                  Apr 5 at 17:39


















                                                • $begingroup$
                                                  Can you explain?
                                                  $endgroup$
                                                  – dfeuer
                                                  Apr 5 at 6:24






                                                • 1




                                                  $begingroup$
                                                  @dfeuer It's using Robin Ryder's method.
                                                  $endgroup$
                                                  – Ørjan Johansen
                                                  Apr 5 at 17:39
















                                                $begingroup$
                                                Can you explain?
                                                $endgroup$
                                                – dfeuer
                                                Apr 5 at 6:24




                                                $begingroup$
                                                Can you explain?
                                                $endgroup$
                                                – dfeuer
                                                Apr 5 at 6:24




                                                1




                                                1




                                                $begingroup$
                                                @dfeuer It's using Robin Ryder's method.
                                                $endgroup$
                                                – Ørjan Johansen
                                                Apr 5 at 17:39




                                                $begingroup$
                                                @dfeuer It's using Robin Ryder's method.
                                                $endgroup$
                                                – Ørjan Johansen
                                                Apr 5 at 17:39











                                                4












                                                $begingroup$


                                                C# (Visual C# Interactive Compiler), 125 42 38 36 bytes





                                                n=>n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                                                Direct port of @xnor's answer, which is based off of @RobinRyder's solution.



                                                Saved 4 bytes thanks to @Ørjan Johansen!



                                                Saved 2 more thanks to @Arnauld!



                                                Try it online!






                                                share|improve this answer











                                                $endgroup$









                                                • 1




                                                  $begingroup$
                                                  I found a variation that only ties for xnor's languages but helps for this: 38 bytes
                                                  $endgroup$
                                                  – Ørjan Johansen
                                                  Apr 5 at 6:04






                                                • 1




                                                  $begingroup$
                                                  Isn't -~n%6/4>0 just -~n%6>3?
                                                  $endgroup$
                                                  – Arnauld
                                                  Apr 6 at 9:55










                                                • $begingroup$
                                                  BTW, this is a JavaScript polyglot.
                                                  $endgroup$
                                                  – Arnauld
                                                  Apr 7 at 7:55
















                                                4












                                                $begingroup$


                                                C# (Visual C# Interactive Compiler), 125 42 38 36 bytes





                                                n=>n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                                                Direct port of @xnor's answer, which is based off of @RobinRyder's solution.



                                                Saved 4 bytes thanks to @Ørjan Johansen!



                                                Saved 2 more thanks to @Arnauld!



                                                Try it online!






                                                share|improve this answer











                                                $endgroup$









                                                • 1




                                                  $begingroup$
                                                  I found a variation that only ties for xnor's languages but helps for this: 38 bytes
                                                  $endgroup$
                                                  – Ørjan Johansen
                                                  Apr 5 at 6:04






                                                • 1




                                                  $begingroup$
                                                  Isn't -~n%6/4>0 just -~n%6>3?
                                                  $endgroup$
                                                  – Arnauld
                                                  Apr 6 at 9:55










                                                • $begingroup$
                                                  BTW, this is a JavaScript polyglot.
                                                  $endgroup$
                                                  – Arnauld
                                                  Apr 7 at 7:55














                                                4












                                                4








                                                4





                                                $begingroup$


                                                C# (Visual C# Interactive Compiler), 125 42 38 36 bytes





                                                n=>n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                                                Direct port of @xnor's answer, which is based off of @RobinRyder's solution.



                                                Saved 4 bytes thanks to @Ørjan Johansen!



                                                Saved 2 more thanks to @Arnauld!



                                                Try it online!






                                                share|improve this answer











                                                $endgroup$




                                                C# (Visual C# Interactive Compiler), 125 42 38 36 bytes





                                                n=>n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                                                Direct port of @xnor's answer, which is based off of @RobinRyder's solution.



                                                Saved 4 bytes thanks to @Ørjan Johansen!



                                                Saved 2 more thanks to @Arnauld!



                                                Try it online!







                                                share|improve this answer














                                                share|improve this answer



                                                share|improve this answer








                                                edited Apr 6 at 21:13

























                                                answered Apr 4 at 16:33









                                                Embodiment of IgnoranceEmbodiment of Ignorance

                                                3,024127




                                                3,024127








                                                • 1




                                                  $begingroup$
                                                  I found a variation that only ties for xnor's languages but helps for this: 38 bytes
                                                  $endgroup$
                                                  – Ørjan Johansen
                                                  Apr 5 at 6:04






                                                • 1




                                                  $begingroup$
                                                  Isn't -~n%6/4>0 just -~n%6>3?
                                                  $endgroup$
                                                  – Arnauld
                                                  Apr 6 at 9:55










                                                • $begingroup$
                                                  BTW, this is a JavaScript polyglot.
                                                  $endgroup$
                                                  – Arnauld
                                                  Apr 7 at 7:55














                                                • 1




                                                  $begingroup$
                                                  I found a variation that only ties for xnor's languages but helps for this: 38 bytes
                                                  $endgroup$
                                                  – Ørjan Johansen
                                                  Apr 5 at 6:04






                                                • 1




                                                  $begingroup$
                                                  Isn't -~n%6/4>0 just -~n%6>3?
                                                  $endgroup$
                                                  – Arnauld
                                                  Apr 6 at 9:55










                                                • $begingroup$
                                                  BTW, this is a JavaScript polyglot.
                                                  $endgroup$
                                                  – Arnauld
                                                  Apr 7 at 7:55








                                                1




                                                1




                                                $begingroup$
                                                I found a variation that only ties for xnor's languages but helps for this: 38 bytes
                                                $endgroup$
                                                – Ørjan Johansen
                                                Apr 5 at 6:04




                                                $begingroup$
                                                I found a variation that only ties for xnor's languages but helps for this: 38 bytes
                                                $endgroup$
                                                – Ørjan Johansen
                                                Apr 5 at 6:04




                                                1




                                                1




                                                $begingroup$
                                                Isn't -~n%6/4>0 just -~n%6>3?
                                                $endgroup$
                                                – Arnauld
                                                Apr 6 at 9:55




                                                $begingroup$
                                                Isn't -~n%6/4>0 just -~n%6>3?
                                                $endgroup$
                                                – Arnauld
                                                Apr 6 at 9:55












                                                $begingroup$
                                                BTW, this is a JavaScript polyglot.
                                                $endgroup$
                                                – Arnauld
                                                Apr 7 at 7:55




                                                $begingroup$
                                                BTW, this is a JavaScript polyglot.
                                                $endgroup$
                                                – Arnauld
                                                Apr 7 at 7:55











                                                3












                                                $begingroup$


                                                Wolfram Language (Mathematica), 67 bytes



                                                !FreeQ[Sort/@Table[R[#+k],{k,209}],Sort@R@#]&
                                                R@n_:=n~Mod~{2,3,5,7}


                                                Try it online!






                                                share|improve this answer











                                                $endgroup$


















                                                  3












                                                  $begingroup$


                                                  Wolfram Language (Mathematica), 67 bytes



                                                  !FreeQ[Sort/@Table[R[#+k],{k,209}],Sort@R@#]&
                                                  R@n_:=n~Mod~{2,3,5,7}


                                                  Try it online!






                                                  share|improve this answer











                                                  $endgroup$
















                                                    3












                                                    3








                                                    3





                                                    $begingroup$


                                                    Wolfram Language (Mathematica), 67 bytes



                                                    !FreeQ[Sort/@Table[R[#+k],{k,209}],Sort@R@#]&
                                                    R@n_:=n~Mod~{2,3,5,7}


                                                    Try it online!






                                                    share|improve this answer











                                                    $endgroup$




                                                    Wolfram Language (Mathematica), 67 bytes



                                                    !FreeQ[Sort/@Table[R[#+k],{k,209}],Sort@R@#]&
                                                    R@n_:=n~Mod~{2,3,5,7}


                                                    Try it online!







                                                    share|improve this answer














                                                    share|improve this answer



                                                    share|improve this answer








                                                    edited Apr 4 at 16:00

























                                                    answered Apr 4 at 15:53









                                                    J42161217J42161217

                                                    14.3k21354




                                                    14.3k21354























                                                        2












                                                        $begingroup$


                                                        Ruby, 54 bytes





                                                        ->n{[2,3,5,7].each_cons(2).any?{|l,h|n%l!=n%h&&n%h<l}}


                                                        Try it online!



                                                        Uses Robin Ryder's clever solution.






                                                        share|improve this answer









                                                        $endgroup$


















                                                          2












                                                          $begingroup$


                                                          Ruby, 54 bytes





                                                          ->n{[2,3,5,7].each_cons(2).any?{|l,h|n%l!=n%h&&n%h<l}}


                                                          Try it online!



                                                          Uses Robin Ryder's clever solution.






                                                          share|improve this answer









                                                          $endgroup$
















                                                            2












                                                            2








                                                            2





                                                            $begingroup$


                                                            Ruby, 54 bytes





                                                            ->n{[2,3,5,7].each_cons(2).any?{|l,h|n%l!=n%h&&n%h<l}}


                                                            Try it online!



                                                            Uses Robin Ryder's clever solution.






                                                            share|improve this answer









                                                            $endgroup$




                                                            Ruby, 54 bytes





                                                            ->n{[2,3,5,7].each_cons(2).any?{|l,h|n%l!=n%h&&n%h<l}}


                                                            Try it online!



                                                            Uses Robin Ryder's clever solution.







                                                            share|improve this answer












                                                            share|improve this answer



                                                            share|improve this answer










                                                            answered Apr 4 at 18:59









                                                            histocrathistocrat

                                                            19.2k43173




                                                            19.2k43173























                                                                2












                                                                $begingroup$


                                                                Java (JDK), 36 bytes





                                                                n->n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                                                                Try it online!



                                                                Credits




                                                                • Port of xnor's solution, improved by Ørjan Johansen.






                                                                share|improve this answer











                                                                $endgroup$


















                                                                  2












                                                                  $begingroup$


                                                                  Java (JDK), 36 bytes





                                                                  n->n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                                                                  Try it online!



                                                                  Credits




                                                                  • Port of xnor's solution, improved by Ørjan Johansen.






                                                                  share|improve this answer











                                                                  $endgroup$
















                                                                    2












                                                                    2








                                                                    2





                                                                    $begingroup$


                                                                    Java (JDK), 36 bytes





                                                                    n->n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                                                                    Try it online!



                                                                    Credits




                                                                    • Port of xnor's solution, improved by Ørjan Johansen.






                                                                    share|improve this answer











                                                                    $endgroup$




                                                                    Java (JDK), 36 bytes





                                                                    n->n%7<5&5<n%35|n%5<3&3<n%15|-~n%6>3


                                                                    Try it online!



                                                                    Credits




                                                                    • Port of xnor's solution, improved by Ørjan Johansen.







                                                                    share|improve this answer














                                                                    share|improve this answer



                                                                    share|improve this answer








                                                                    edited Apr 8 at 7:43

























                                                                    answered Apr 5 at 9:07









                                                                    Olivier GrégoireOlivier Grégoire

                                                                    9,47511944




                                                                    9,47511944























                                                                        1












                                                                        $begingroup$


                                                                        R, 72 bytes





                                                                        n=scan();b=c(2,3,5,7);for(i in n+1:209)F=F|all(sort(n%%b)==sort(i%%b));F


                                                                        Try it online!






                                                                        share|improve this answer









                                                                        $endgroup$


















                                                                          1












                                                                          $begingroup$


                                                                          R, 72 bytes





                                                                          n=scan();b=c(2,3,5,7);for(i in n+1:209)F=F|all(sort(n%%b)==sort(i%%b));F


                                                                          Try it online!






                                                                          share|improve this answer









                                                                          $endgroup$
















                                                                            1












                                                                            1








                                                                            1





                                                                            $begingroup$


                                                                            R, 72 bytes





                                                                            n=scan();b=c(2,3,5,7);for(i in n+1:209)F=F|all(sort(n%%b)==sort(i%%b));F


                                                                            Try it online!






                                                                            share|improve this answer









                                                                            $endgroup$




                                                                            R, 72 bytes





                                                                            n=scan();b=c(2,3,5,7);for(i in n+1:209)F=F|all(sort(n%%b)==sort(i%%b));F


                                                                            Try it online!







                                                                            share|improve this answer












                                                                            share|improve this answer



                                                                            share|improve this answer










                                                                            answered Apr 4 at 16:42









                                                                            Aaron HaymanAaron Hayman

                                                                            3516




                                                                            3516























                                                                                1












                                                                                $begingroup$


                                                                                PHP, 81 78 72 bytes





                                                                                while($y<3)if($argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u)die(T);


                                                                                A riff on @Robin Ryder's answer. Input is via STDIN, output is 'T' if truthy, and empty '' if falsy.



                                                                                $ echo 3|php -nF euc.php
                                                                                T
                                                                                $ echo 5|php -nF euc.php
                                                                                T
                                                                                $ echo 2019|php -nF euc.php
                                                                                T
                                                                                $ echo 0|php -nF euc.php

                                                                                $ echo 2|php -nF euc.php

                                                                                $ echo 1999|php -nF euc.php


                                                                                Try it online!



                                                                                Or 73 bytes with 1 or 0 response



                                                                                while($y<3)$r|=$argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u;echo$r;



                                                                                $ echo 2019|php -nF euc.php
                                                                                1
                                                                                $ echo 1999|php -nF euc.php
                                                                                0


                                                                                Try it online (all test cases)!



                                                                                Original answer, 133 127 bytes



                                                                                function($n){while(++$k<210)if(($r=function($n){foreach([2,3,5,7]as$d)$o=$n%$d;sort($o);return$o;})($n+$k)==$r($n))return 1;}


                                                                                Try it online!






                                                                                share|improve this answer











                                                                                $endgroup$


















                                                                                  1












                                                                                  $begingroup$


                                                                                  PHP, 81 78 72 bytes





                                                                                  while($y<3)if($argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u)die(T);


                                                                                  A riff on @Robin Ryder's answer. Input is via STDIN, output is 'T' if truthy, and empty '' if falsy.



                                                                                  $ echo 3|php -nF euc.php
                                                                                  T
                                                                                  $ echo 5|php -nF euc.php
                                                                                  T
                                                                                  $ echo 2019|php -nF euc.php
                                                                                  T
                                                                                  $ echo 0|php -nF euc.php

                                                                                  $ echo 2|php -nF euc.php

                                                                                  $ echo 1999|php -nF euc.php


                                                                                  Try it online!



                                                                                  Or 73 bytes with 1 or 0 response



                                                                                  while($y<3)$r|=$argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u;echo$r;



                                                                                  $ echo 2019|php -nF euc.php
                                                                                  1
                                                                                  $ echo 1999|php -nF euc.php
                                                                                  0


                                                                                  Try it online (all test cases)!



                                                                                  Original answer, 133 127 bytes



                                                                                  function($n){while(++$k<210)if(($r=function($n){foreach([2,3,5,7]as$d)$o=$n%$d;sort($o);return$o;})($n+$k)==$r($n))return 1;}


                                                                                  Try it online!






                                                                                  share|improve this answer











                                                                                  $endgroup$
















                                                                                    1












                                                                                    1








                                                                                    1





                                                                                    $begingroup$


                                                                                    PHP, 81 78 72 bytes





                                                                                    while($y<3)if($argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u)die(T);


                                                                                    A riff on @Robin Ryder's answer. Input is via STDIN, output is 'T' if truthy, and empty '' if falsy.



                                                                                    $ echo 3|php -nF euc.php
                                                                                    T
                                                                                    $ echo 5|php -nF euc.php
                                                                                    T
                                                                                    $ echo 2019|php -nF euc.php
                                                                                    T
                                                                                    $ echo 0|php -nF euc.php

                                                                                    $ echo 2|php -nF euc.php

                                                                                    $ echo 1999|php -nF euc.php


                                                                                    Try it online!



                                                                                    Or 73 bytes with 1 or 0 response



                                                                                    while($y<3)$r|=$argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u;echo$r;



                                                                                    $ echo 2019|php -nF euc.php
                                                                                    1
                                                                                    $ echo 1999|php -nF euc.php
                                                                                    0


                                                                                    Try it online (all test cases)!



                                                                                    Original answer, 133 127 bytes



                                                                                    function($n){while(++$k<210)if(($r=function($n){foreach([2,3,5,7]as$d)$o=$n%$d;sort($o);return$o;})($n+$k)==$r($n))return 1;}


                                                                                    Try it online!






                                                                                    share|improve this answer











                                                                                    $endgroup$




                                                                                    PHP, 81 78 72 bytes





                                                                                    while($y<3)if($argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u)die(T);


                                                                                    A riff on @Robin Ryder's answer. Input is via STDIN, output is 'T' if truthy, and empty '' if falsy.



                                                                                    $ echo 3|php -nF euc.php
                                                                                    T
                                                                                    $ echo 5|php -nF euc.php
                                                                                    T
                                                                                    $ echo 2019|php -nF euc.php
                                                                                    T
                                                                                    $ echo 0|php -nF euc.php

                                                                                    $ echo 2|php -nF euc.php

                                                                                    $ echo 1999|php -nF euc.php


                                                                                    Try it online!



                                                                                    Or 73 bytes with 1 or 0 response



                                                                                    while($y<3)$r|=$argn%($u='235'[$y])!=($b=$argn%'357'[$y++])&$b<$u;echo$r;



                                                                                    $ echo 2019|php -nF euc.php
                                                                                    1
                                                                                    $ echo 1999|php -nF euc.php
                                                                                    0


                                                                                    Try it online (all test cases)!



                                                                                    Original answer, 133 127 bytes



                                                                                    function($n){while(++$k<210)if(($r=function($n){foreach([2,3,5,7]as$d)$o=$n%$d;sort($o);return$o;})($n+$k)==$r($n))return 1;}


                                                                                    Try it online!







                                                                                    share|improve this answer














                                                                                    share|improve this answer



                                                                                    share|improve this answer








                                                                                    edited Apr 4 at 19:16

























                                                                                    answered Apr 4 at 16:01









                                                                                    gwaughgwaugh

                                                                                    2,4281519




                                                                                    2,4281519























                                                                                        1












                                                                                        $begingroup$


                                                                                        Python 3, 69 bytes





                                                                                        lambda x:int('4LR2991ODO5GS2974QWH22YTLL3E3I6TDADQG87I0',36)&1<<x%210


                                                                                        Try it online!



                                                                                        Hardcoded






                                                                                        share|improve this answer









                                                                                        $endgroup$


















                                                                                          1












                                                                                          $begingroup$


                                                                                          Python 3, 69 bytes





                                                                                          lambda x:int('4LR2991ODO5GS2974QWH22YTLL3E3I6TDADQG87I0',36)&1<<x%210


                                                                                          Try it online!



                                                                                          Hardcoded






                                                                                          share|improve this answer









                                                                                          $endgroup$
















                                                                                            1












                                                                                            1








                                                                                            1





                                                                                            $begingroup$


                                                                                            Python 3, 69 bytes





                                                                                            lambda x:int('4LR2991ODO5GS2974QWH22YTLL3E3I6TDADQG87I0',36)&1<<x%210


                                                                                            Try it online!



                                                                                            Hardcoded






                                                                                            share|improve this answer









                                                                                            $endgroup$




                                                                                            Python 3, 69 bytes





                                                                                            lambda x:int('4LR2991ODO5GS2974QWH22YTLL3E3I6TDADQG87I0',36)&1<<x%210


                                                                                            Try it online!



                                                                                            Hardcoded







                                                                                            share|improve this answer












                                                                                            share|improve this answer



                                                                                            share|improve this answer










                                                                                            answered Apr 4 at 22:17









                                                                                            attinatattinat

                                                                                            60917




                                                                                            60917























                                                                                                1












                                                                                                $begingroup$


                                                                                                05AB1E, 16 bytes



                                                                                                Ƶ.L+ε‚ε4Åp%{}Ë}à


                                                                                                Try it online or verify all test cases.



                                                                                                Explanation:





                                                                                                Ƶ.L          # Create a list in the range [1,209] (which is k)
                                                                                                + # Add the (implicit) input to each (which is n+k)
                                                                                                ε # Map each value to:
                                                                                                ‚ # Pair it with the (implicit) input
                                                                                                ε # Map both to:
                                                                                                4Åp # Get the first 4 primes: [2,3,5,7]
                                                                                                % # Modulo the current number by each of these four (now we have R_n and R_n+k)
                                                                                                { # Sort the list
                                                                                                }Ë # After the inner map: check if both sorted lists are equal
                                                                                                }à # After the outer map: check if any are truthy by taking the maximum
                                                                                                # (which is output implicitly as result)


                                                                                                See this 05AB1E tip of mine (section How to compress large integers?) to understand why Ƶ. is 209.






                                                                                                share|improve this answer









                                                                                                $endgroup$


















                                                                                                  1












                                                                                                  $begingroup$


                                                                                                  05AB1E, 16 bytes



                                                                                                  Ƶ.L+ε‚ε4Åp%{}Ë}à


                                                                                                  Try it online or verify all test cases.



                                                                                                  Explanation:





                                                                                                  Ƶ.L          # Create a list in the range [1,209] (which is k)
                                                                                                  + # Add the (implicit) input to each (which is n+k)
                                                                                                  ε # Map each value to:
                                                                                                  ‚ # Pair it with the (implicit) input
                                                                                                  ε # Map both to:
                                                                                                  4Åp # Get the first 4 primes: [2,3,5,7]
                                                                                                  % # Modulo the current number by each of these four (now we have R_n and R_n+k)
                                                                                                  { # Sort the list
                                                                                                  }Ë # After the inner map: check if both sorted lists are equal
                                                                                                  }à # After the outer map: check if any are truthy by taking the maximum
                                                                                                  # (which is output implicitly as result)


                                                                                                  See this 05AB1E tip of mine (section How to compress large integers?) to understand why Ƶ. is 209.






                                                                                                  share|improve this answer









                                                                                                  $endgroup$
















                                                                                                    1












                                                                                                    1








                                                                                                    1





                                                                                                    $begingroup$


                                                                                                    05AB1E, 16 bytes



                                                                                                    Ƶ.L+ε‚ε4Åp%{}Ë}à


                                                                                                    Try it online or verify all test cases.



                                                                                                    Explanation:





                                                                                                    Ƶ.L          # Create a list in the range [1,209] (which is k)
                                                                                                    + # Add the (implicit) input to each (which is n+k)
                                                                                                    ε # Map each value to:
                                                                                                    ‚ # Pair it with the (implicit) input
                                                                                                    ε # Map both to:
                                                                                                    4Åp # Get the first 4 primes: [2,3,5,7]
                                                                                                    % # Modulo the current number by each of these four (now we have R_n and R_n+k)
                                                                                                    { # Sort the list
                                                                                                    }Ë # After the inner map: check if both sorted lists are equal
                                                                                                    }à # After the outer map: check if any are truthy by taking the maximum
                                                                                                    # (which is output implicitly as result)


                                                                                                    See this 05AB1E tip of mine (section How to compress large integers?) to understand why Ƶ. is 209.






                                                                                                    share|improve this answer









                                                                                                    $endgroup$




                                                                                                    05AB1E, 16 bytes



                                                                                                    Ƶ.L+ε‚ε4Åp%{}Ë}à


                                                                                                    Try it online or verify all test cases.



                                                                                                    Explanation:





                                                                                                    Ƶ.L          # Create a list in the range [1,209] (which is k)
                                                                                                    + # Add the (implicit) input to each (which is n+k)
                                                                                                    ε # Map each value to:
                                                                                                    ‚ # Pair it with the (implicit) input
                                                                                                    ε # Map both to:
                                                                                                    4Åp # Get the first 4 primes: [2,3,5,7]
                                                                                                    % # Modulo the current number by each of these four (now we have R_n and R_n+k)
                                                                                                    { # Sort the list
                                                                                                    }Ë # After the inner map: check if both sorted lists are equal
                                                                                                    }à # After the outer map: check if any are truthy by taking the maximum
                                                                                                    # (which is output implicitly as result)


                                                                                                    See this 05AB1E tip of mine (section How to compress large integers?) to understand why Ƶ. is 209.







                                                                                                    share|improve this answer












                                                                                                    share|improve this answer



                                                                                                    share|improve this answer










                                                                                                    answered Apr 5 at 7:29









                                                                                                    Kevin CruijssenKevin Cruijssen

                                                                                                    43.3k573222




                                                                                                    43.3k573222























                                                                                                        1












                                                                                                        $begingroup$


                                                                                                        J, 40 bytes



                                                                                                        1 e.(>:+i.@209)-:&(/:~)&(2 3 5 7&|"1 0)]


                                                                                                        Try it online!



                                                                                                        Brute force...






                                                                                                        share|improve this answer









                                                                                                        $endgroup$


















                                                                                                          1












                                                                                                          $begingroup$


                                                                                                          J, 40 bytes



                                                                                                          1 e.(>:+i.@209)-:&(/:~)&(2 3 5 7&|"1 0)]


                                                                                                          Try it online!



                                                                                                          Brute force...






                                                                                                          share|improve this answer









                                                                                                          $endgroup$
















                                                                                                            1












                                                                                                            1








                                                                                                            1





                                                                                                            $begingroup$


                                                                                                            J, 40 bytes



                                                                                                            1 e.(>:+i.@209)-:&(/:~)&(2 3 5 7&|"1 0)]


                                                                                                            Try it online!



                                                                                                            Brute force...






                                                                                                            share|improve this answer









                                                                                                            $endgroup$




                                                                                                            J, 40 bytes



                                                                                                            1 e.(>:+i.@209)-:&(/:~)&(2 3 5 7&|"1 0)]


                                                                                                            Try it online!



                                                                                                            Brute force...







                                                                                                            share|improve this answer












                                                                                                            share|improve this answer



                                                                                                            share|improve this answer










                                                                                                            answered Apr 5 at 8:28









                                                                                                            Galen IvanovGalen Ivanov

                                                                                                            7,54211034




                                                                                                            7,54211034























                                                                                                                1












                                                                                                                $begingroup$


                                                                                                                Wolfram Language (Mathematica), 56 bytes



                                                                                                                Or@@(Min[s-#]>0&/@Rest@Permutations@Mod[#,s={2,3,5,7}])&


                                                                                                                Try it online!



                                                                                                                Finds all non-identity permutations of the remainders of the input modulo 2, 3, 5, 7, and checks if any of them are below {2,3,5,7} in each coordinate. Note that Or@@{} is False.






                                                                                                                share|improve this answer









                                                                                                                $endgroup$


















                                                                                                                  1












                                                                                                                  $begingroup$


                                                                                                                  Wolfram Language (Mathematica), 56 bytes



                                                                                                                  Or@@(Min[s-#]>0&/@Rest@Permutations@Mod[#,s={2,3,5,7}])&


                                                                                                                  Try it online!



                                                                                                                  Finds all non-identity permutations of the remainders of the input modulo 2, 3, 5, 7, and checks if any of them are below {2,3,5,7} in each coordinate. Note that Or@@{} is False.






                                                                                                                  share|improve this answer









                                                                                                                  $endgroup$
















                                                                                                                    1












                                                                                                                    1








                                                                                                                    1





                                                                                                                    $begingroup$


                                                                                                                    Wolfram Language (Mathematica), 56 bytes



                                                                                                                    Or@@(Min[s-#]>0&/@Rest@Permutations@Mod[#,s={2,3,5,7}])&


                                                                                                                    Try it online!



                                                                                                                    Finds all non-identity permutations of the remainders of the input modulo 2, 3, 5, 7, and checks if any of them are below {2,3,5,7} in each coordinate. Note that Or@@{} is False.






                                                                                                                    share|improve this answer









                                                                                                                    $endgroup$




                                                                                                                    Wolfram Language (Mathematica), 56 bytes



                                                                                                                    Or@@(Min[s-#]>0&/@Rest@Permutations@Mod[#,s={2,3,5,7}])&


                                                                                                                    Try it online!



                                                                                                                    Finds all non-identity permutations of the remainders of the input modulo 2, 3, 5, 7, and checks if any of them are below {2,3,5,7} in each coordinate. Note that Or@@{} is False.







                                                                                                                    share|improve this answer












                                                                                                                    share|improve this answer



                                                                                                                    share|improve this answer










                                                                                                                    answered Apr 6 at 0:57









                                                                                                                    Misha LavrovMisha Lavrov

                                                                                                                    4,271424




                                                                                                                    4,271424























                                                                                                                        1












                                                                                                                        $begingroup$


                                                                                                                        Jelly, 15 bytes



                                                                                                                        8ÆR©PḶ+%Ṣ¥€®ċḢ$


                                                                                                                        Try it online!



                                                                                                                        I’m sure there’s a golfier answer. I’ve interpreted a truthy value as being anything that isn’t zero, so here it’s the number of possible values of k. If it needs to be two distinct values that costs me a further byte.



                                                                                                                        Explanation



                                                                                                                        8ÆR             | Primes less than 8 [2,3,5,7]
                                                                                                                        © | Copy to register
                                                                                                                        P | Product [210]
                                                                                                                        Ḷ | Lowered range [0, 1, ..., 208, 209]
                                                                                                                        + | Add to input
                                                                                                                        ¥€ | For each of these 210 numbers...
                                                                                                                        % ® | Modulo 2, 3, 5, 7
                                                                                                                        Ṣ | And sort
                                                                                                                        ċḢ$ | Count how many match the first (input) number’s remainders





                                                                                                                        share|improve this answer











                                                                                                                        $endgroup$









                                                                                                                        • 1




                                                                                                                          $begingroup$
                                                                                                                          All good regarding truthy vs falsey. Using the meta agreed definition of truthy and falsey (effectively "what does the language's if-else construct do if there is one) zero is falsey and non-zeros are truthy (? is the if-else construct in Jelly; for some languages it's a harder question).
                                                                                                                          $endgroup$
                                                                                                                          – Jonathan Allan
                                                                                                                          Apr 4 at 18:08










                                                                                                                        • $begingroup$
                                                                                                                          Oh, and you could get distinct values for no cost with Ḣe$ if you wanted :)
                                                                                                                          $endgroup$
                                                                                                                          – Jonathan Allan
                                                                                                                          Apr 4 at 18:11










                                                                                                                        • $begingroup$
                                                                                                                          @JonathanAllan yes of course, thanks. :)
                                                                                                                          $endgroup$
                                                                                                                          – Nick Kennedy
                                                                                                                          Apr 4 at 18:12


















                                                                                                                        1












                                                                                                                        $begingroup$


                                                                                                                        Jelly, 15 bytes



                                                                                                                        8ÆR©PḶ+%Ṣ¥€®ċḢ$


                                                                                                                        Try it online!



                                                                                                                        I’m sure there’s a golfier answer. I’ve interpreted a truthy value as being anything that isn’t zero, so here it’s the number of possible values of k. If it needs to be two distinct values that costs me a further byte.



                                                                                                                        Explanation



                                                                                                                        8ÆR             | Primes less than 8 [2,3,5,7]
                                                                                                                        © | Copy to register
                                                                                                                        P | Product [210]
                                                                                                                        Ḷ | Lowered range [0, 1, ..., 208, 209]
                                                                                                                        + | Add to input
                                                                                                                        ¥€ | For each of these 210 numbers...
                                                                                                                        % ® | Modulo 2, 3, 5, 7
                                                                                                                        Ṣ | And sort
                                                                                                                        ċḢ$ | Count how many match the first (input) number’s remainders





                                                                                                                        share|improve this answer











                                                                                                                        $endgroup$









                                                                                                                        • 1




                                                                                                                          $begingroup$
                                                                                                                          All good regarding truthy vs falsey. Using the meta agreed definition of truthy and falsey (effectively "what does the language's if-else construct do if there is one) zero is falsey and non-zeros are truthy (? is the if-else construct in Jelly; for some languages it's a harder question).
                                                                                                                          $endgroup$
                                                                                                                          – Jonathan Allan
                                                                                                                          Apr 4 at 18:08










                                                                                                                        • $begingroup$
                                                                                                                          Oh, and you could get distinct values for no cost with Ḣe$ if you wanted :)
                                                                                                                          $endgroup$
                                                                                                                          – Jonathan Allan
                                                                                                                          Apr 4 at 18:11










                                                                                                                        • $begingroup$
                                                                                                                          @JonathanAllan yes of course, thanks. :)
                                                                                                                          $endgroup$
                                                                                                                          – Nick Kennedy
                                                                                                                          Apr 4 at 18:12
















                                                                                                                        1












                                                                                                                        1








                                                                                                                        1





                                                                                                                        $begingroup$


                                                                                                                        Jelly, 15 bytes



                                                                                                                        8ÆR©PḶ+%Ṣ¥€®ċḢ$


                                                                                                                        Try it online!



                                                                                                                        I’m sure there’s a golfier answer. I’ve interpreted a truthy value as being anything that isn’t zero, so here it’s the number of possible values of k. If it needs to be two distinct values that costs me a further byte.



                                                                                                                        Explanation



                                                                                                                        8ÆR             | Primes less than 8 [2,3,5,7]
                                                                                                                        © | Copy to register
                                                                                                                        P | Product [210]
                                                                                                                        Ḷ | Lowered range [0, 1, ..., 208, 209]
                                                                                                                        + | Add to input
                                                                                                                        ¥€ | For each of these 210 numbers...
                                                                                                                        % ® | Modulo 2, 3, 5, 7
                                                                                                                        Ṣ | And sort
                                                                                                                        ċḢ$ | Count how many match the first (input) number’s remainders





                                                                                                                        share|improve this answer











                                                                                                                        $endgroup$




                                                                                                                        Jelly, 15 bytes



                                                                                                                        8ÆR©PḶ+%Ṣ¥€®ċḢ$


                                                                                                                        Try it online!



                                                                                                                        I’m sure there’s a golfier answer. I’ve interpreted a truthy value as being anything that isn’t zero, so here it’s the number of possible values of k. If it needs to be two distinct values that costs me a further byte.



                                                                                                                        Explanation



                                                                                                                        8ÆR             | Primes less than 8 [2,3,5,7]
                                                                                                                        © | Copy to register
                                                                                                                        P | Product [210]
                                                                                                                        Ḷ | Lowered range [0, 1, ..., 208, 209]
                                                                                                                        + | Add to input
                                                                                                                        ¥€ | For each of these 210 numbers...
                                                                                                                        % ® | Modulo 2, 3, 5, 7
                                                                                                                        Ṣ | And sort
                                                                                                                        ċḢ$ | Count how many match the first (input) number’s remainders






                                                                                                                        share|improve this answer














                                                                                                                        share|improve this answer



                                                                                                                        share|improve this answer








                                                                                                                        edited Apr 9 at 11:41

























                                                                                                                        answered Apr 4 at 17:59









                                                                                                                        Nick KennedyNick Kennedy

                                                                                                                        1,87149




                                                                                                                        1,87149








                                                                                                                        • 1




                                                                                                                          $begingroup$
                                                                                                                          All good regarding truthy vs falsey. Using the meta agreed definition of truthy and falsey (effectively "what does the language's if-else construct do if there is one) zero is falsey and non-zeros are truthy (? is the if-else construct in Jelly; for some languages it's a harder question).
                                                                                                                          $endgroup$
                                                                                                                          – Jonathan Allan
                                                                                                                          Apr 4 at 18:08










                                                                                                                        • $begingroup$
                                                                                                                          Oh, and you could get distinct values for no cost with Ḣe$ if you wanted :)
                                                                                                                          $endgroup$
                                                                                                                          – Jonathan Allan
                                                                                                                          Apr 4 at 18:11










                                                                                                                        • $begingroup$
                                                                                                                          @JonathanAllan yes of course, thanks. :)
                                                                                                                          $endgroup$
                                                                                                                          – Nick Kennedy
                                                                                                                          Apr 4 at 18:12
















                                                                                                                        • 1




                                                                                                                          $begingroup$
                                                                                                                          All good regarding truthy vs falsey. Using the meta agreed definition of truthy and falsey (effectively "what does the language's if-else construct do if there is one) zero is falsey and non-zeros are truthy (? is the if-else construct in Jelly; for some languages it's a harder question).
                                                                                                                          $endgroup$
                                                                                                                          – Jonathan Allan
                                                                                                                          Apr 4 at 18:08










                                                                                                                        • $begingroup$
                                                                                                                          Oh, and you could get distinct values for no cost with Ḣe$ if you wanted :)
                                                                                                                          $endgroup$
                                                                                                                          – Jonathan Allan
                                                                                                                          Apr 4 at 18:11










                                                                                                                        • $begingroup$
                                                                                                                          @JonathanAllan yes of course, thanks. :)
                                                                                                                          $endgroup$
                                                                                                                          – Nick Kennedy
                                                                                                                          Apr 4 at 18:12










                                                                                                                        1




                                                                                                                        1




                                                                                                                        $begingroup$
                                                                                                                        All good regarding truthy vs falsey. Using the meta agreed definition of truthy and falsey (effectively "what does the language's if-else construct do if there is one) zero is falsey and non-zeros are truthy (? is the if-else construct in Jelly; for some languages it's a harder question).
                                                                                                                        $endgroup$
                                                                                                                        – Jonathan Allan
                                                                                                                        Apr 4 at 18:08




                                                                                                                        $begingroup$
                                                                                                                        All good regarding truthy vs falsey. Using the meta agreed definition of truthy and falsey (effectively "what does the language's if-else construct do if there is one) zero is falsey and non-zeros are truthy (? is the if-else construct in Jelly; for some languages it's a harder question).
                                                                                                                        $endgroup$
                                                                                                                        – Jonathan Allan
                                                                                                                        Apr 4 at 18:08












                                                                                                                        $begingroup$
                                                                                                                        Oh, and you could get distinct values for no cost with Ḣe$ if you wanted :)
                                                                                                                        $endgroup$
                                                                                                                        – Jonathan Allan
                                                                                                                        Apr 4 at 18:11




                                                                                                                        $begingroup$
                                                                                                                        Oh, and you could get distinct values for no cost with Ḣe$ if you wanted :)
                                                                                                                        $endgroup$
                                                                                                                        – Jonathan Allan
                                                                                                                        Apr 4 at 18:11












                                                                                                                        $begingroup$
                                                                                                                        @JonathanAllan yes of course, thanks. :)
                                                                                                                        $endgroup$
                                                                                                                        – Nick Kennedy
                                                                                                                        Apr 4 at 18:12






                                                                                                                        $begingroup$
                                                                                                                        @JonathanAllan yes of course, thanks. :)
                                                                                                                        $endgroup$
                                                                                                                        – Nick Kennedy
                                                                                                                        Apr 4 at 18:12




















                                                                                                                        draft saved

                                                                                                                        draft discarded




















































                                                                                                                        If this is an answer to a challenge…




                                                                                                                        • …Be sure to follow the challenge specification. However, please refrain from exploiting obvious loopholes. Answers abusing any of the standard loopholes are considered invalid. If you think a specification is unclear or underspecified, comment on the question instead.


                                                                                                                        • …Try to optimize your score. For instance, answers to code-golf challenges should attempt to be as short as possible. You can always include a readable version of the code in addition to the competitive one.
                                                                                                                          Explanations of your answer make it more interesting to read and are very much encouraged.


                                                                                                                        • …Include a short header which indicates the language(s) of your code and its score, as defined by the challenge.



                                                                                                                        More generally…




                                                                                                                        • …Please make sure to answer the question and provide sufficient detail.


                                                                                                                        • …Avoid asking for help, clarification or responding to other answers (use comments instead).





                                                                                                                        draft saved


                                                                                                                        draft discarded














                                                                                                                        StackExchange.ready(
                                                                                                                        function () {
                                                                                                                        StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcodegolf.stackexchange.com%2fquestions%2f182669%2fdo-i-have-a-twin-with-permutated-remainders%23new-answer', 'question_page');
                                                                                                                        }
                                                                                                                        );

                                                                                                                        Post as a guest















                                                                                                                        Required, but never shown





















































                                                                                                                        Required, but never shown














                                                                                                                        Required, but never shown












                                                                                                                        Required, but never shown







                                                                                                                        Required, but never shown

































                                                                                                                        Required, but never shown














                                                                                                                        Required, but never shown












                                                                                                                        Required, but never shown







                                                                                                                        Required, but never shown







                                                                                                                        Popular posts from this blog

                                                                                                                        "Incorrect syntax near the keyword 'ON'. (on update cascade, on delete cascade,)

                                                                                                                        Alcedinidae

                                                                                                                        Origin of the phrase “under your belt”?