Create the numbers 1 - 30 using the digits 2, 0, 1, 9 in this particular order!












9














Inspired by the last year's "2018 four 4s challenge", I thought it's time to welcome 2019 by a similar challenge. This time you have to use the digits 2, 0, 1, 9 in this particular order to create the numbers 1 - 30.



The rules haven't changed:




  • Use all four digits exactly once in the order 2-0-1-9.

  • Allowed operations: $+, -, cdot, div, !$ (factorial), $!!$ (double factorial), square root, exponentiation.

  • Parentheses and grouping (e.g. "19") are also allowed.

  • Squaring uses the digit 2, so expressions using multiple 2's, e. g. $2^2$ or $1^2+2^9$, are not allowed.

  • The modulus operator $(%, mod)$ is not allowed.

  • Rounding (e.g. 201/9=22) is not allowed.


I'm curious to see your creative solutions!



May each day of 2019 bring happiness, good cheer, and sweet surprises to you and all your dear ones!



Happy New Year and greetings from Germany!
André










share|improve this question






















  • Will you be giving a green check to someone?
    – flashstorm
    2 days ago










  • Of course I'll do.
    – André
    2 days ago
















9














Inspired by the last year's "2018 four 4s challenge", I thought it's time to welcome 2019 by a similar challenge. This time you have to use the digits 2, 0, 1, 9 in this particular order to create the numbers 1 - 30.



The rules haven't changed:




  • Use all four digits exactly once in the order 2-0-1-9.

  • Allowed operations: $+, -, cdot, div, !$ (factorial), $!!$ (double factorial), square root, exponentiation.

  • Parentheses and grouping (e.g. "19") are also allowed.

  • Squaring uses the digit 2, so expressions using multiple 2's, e. g. $2^2$ or $1^2+2^9$, are not allowed.

  • The modulus operator $(%, mod)$ is not allowed.

  • Rounding (e.g. 201/9=22) is not allowed.


I'm curious to see your creative solutions!



May each day of 2019 bring happiness, good cheer, and sweet surprises to you and all your dear ones!



Happy New Year and greetings from Germany!
André










share|improve this question






















  • Will you be giving a green check to someone?
    – flashstorm
    2 days ago










  • Of course I'll do.
    – André
    2 days ago














9












9








9


1





Inspired by the last year's "2018 four 4s challenge", I thought it's time to welcome 2019 by a similar challenge. This time you have to use the digits 2, 0, 1, 9 in this particular order to create the numbers 1 - 30.



The rules haven't changed:




  • Use all four digits exactly once in the order 2-0-1-9.

  • Allowed operations: $+, -, cdot, div, !$ (factorial), $!!$ (double factorial), square root, exponentiation.

  • Parentheses and grouping (e.g. "19") are also allowed.

  • Squaring uses the digit 2, so expressions using multiple 2's, e. g. $2^2$ or $1^2+2^9$, are not allowed.

  • The modulus operator $(%, mod)$ is not allowed.

  • Rounding (e.g. 201/9=22) is not allowed.


I'm curious to see your creative solutions!



May each day of 2019 bring happiness, good cheer, and sweet surprises to you and all your dear ones!



Happy New Year and greetings from Germany!
André










share|improve this question













Inspired by the last year's "2018 four 4s challenge", I thought it's time to welcome 2019 by a similar challenge. This time you have to use the digits 2, 0, 1, 9 in this particular order to create the numbers 1 - 30.



The rules haven't changed:




  • Use all four digits exactly once in the order 2-0-1-9.

  • Allowed operations: $+, -, cdot, div, !$ (factorial), $!!$ (double factorial), square root, exponentiation.

  • Parentheses and grouping (e.g. "19") are also allowed.

  • Squaring uses the digit 2, so expressions using multiple 2's, e. g. $2^2$ or $1^2+2^9$, are not allowed.

  • The modulus operator $(%, mod)$ is not allowed.

  • Rounding (e.g. 201/9=22) is not allowed.


I'm curious to see your creative solutions!



May each day of 2019 bring happiness, good cheer, and sweet surprises to you and all your dear ones!



Happy New Year and greetings from Germany!
André







formation-of-numbers number-theory






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share|improve this question










asked Dec 31 '18 at 18:28









André

1,183716




1,183716












  • Will you be giving a green check to someone?
    – flashstorm
    2 days ago










  • Of course I'll do.
    – André
    2 days ago


















  • Will you be giving a green check to someone?
    – flashstorm
    2 days ago










  • Of course I'll do.
    – André
    2 days ago
















Will you be giving a green check to someone?
– flashstorm
2 days ago




Will you be giving a green check to someone?
– flashstorm
2 days ago












Of course I'll do.
– André
2 days ago




Of course I'll do.
– André
2 days ago










5 Answers
5






active

oldest

votes


















4














1




1 = 2^(0*19)




2




2 = 2 + (0*19)




3




3 = 2 + 0!^19




4




4 = 2 ^ (0! + 1 ^ 9)




5




-((2 + 0! + 1) - 9)




6




-((2 + 0 + 1) - 9))




7




-((2 + 0*1 - 9))




8




-((2 - 01) - 9)




9




2*0*1 + 9




10




2*0 + 1 + 9




11




2 + 0*1 + 9




12




2 + 0 + 1 + 9




13




2 + 0! + 1 + 9




14




(2 + 0!)! - 1 + 9




15




(2 + 0 + 1)! + 9




16




(2 + 0!)! + 1 + 9




17




20 - (1 * sqrt(9))




18




(2 + (0 * 1)) * 9




19




20 - 1^9




20




20 * 1^9




21




20 + 1^9




22




2 + 0! + 19




23




20 + 1 * sqrt(9)




24




20 + 1 + sqrt(9)




25




2 || (0! + 1 + sqrt (9))




explained:




Ok, this one needs explanation. The operation for "grouping" is known as concatenation and represented by ||. Basically this means push the digits together: 2 || 0 = 20. However, just like any operation, you can represent either side not by a number but by an equation on its own. So 0! + 1 + sqrt(9) = 5, meaning the above represents 2 || 5, qed.




26




2 || ((0! + 1) * sqrt(9))




27




(2 + 0 + 1) * 9




28




((2 + 0!) || 1) - sqrt(9)




29




(2 + (0 * 1)) || 9




30




20 + 1 + 9







share|improve this answer























  • edited for clarity
    – flashstorm
    Dec 31 '18 at 18:59










  • @flashstorm Um... $3ne 2+0^{19}$
    – Frpzzd
    Dec 31 '18 at 19:13






  • 1




    was missing an !
    – flashstorm
    Dec 31 '18 at 19:19










  • Ding! Fries are done :)
    – flashstorm
    Dec 31 '18 at 19:31



















7















$$1=20-19$$
$$2=2+0cdot 19=20div(1+9)$$
$$3=2cdot 0cdot 1+sqrt{9}=-(2+0+1)!+9$$
$$4=2^{0-1+sqrt{9}}$$
$$5=20div (1+sqrt{9})$$
$$6=(2cdot 0cdot 1+sqrt{9})!$$
$$7=-2-0cdot 1+9$$
$$8=2^{0cdot 1+sqrt{9}}$$
$$9=2cdot 0cdot 1+9$$
$$10=2cdot 0+1+9=20-1-9$$
$$11=2+0cdot 1+9=20-1cdot 9=2^0+1+9$$
$$12=2+0+1+9=20+1-9$$
$$13=2+0!+1+9=2^{0!+1}+9$$
$$14=(2+0!)!-1+9$$
$$15=(2+0+1)!+9$$
$$16=2^{0+1+sqrt{9}}$$
$$17=20-sqrt{1cdot 9}$$
$$18=20+1-sqrt{9}$$
$$19=2cdot 0+19$$
$$20=2^0+19$$
$$21=20+1^9$$
$$22=2cdot (0!+1+9)$$
$$23=20+sqrt{1cdot 9}$$
$$24=2^{0-1+sqrt{9}}!=20+1+sqrt{9}$$
$$25=(2+0!)!+19$$
$$26=2+0+(1+sqrt{9})!$$
$$27=(2+0+1)^{sqrt{9}}$$
$$28=20-1+9$$
$$29=20+1cdot 9=20cdot 1+9$$
$$30=20+1+9$$




DONE!






share|improve this answer























  • All finished now! :D
    – Frpzzd
    Dec 31 '18 at 19:48










  • Great :) But Spoiler-Tags would be nice ;)
    – André
    Dec 31 '18 at 21:23












  • @André Oh, sorry! I can't figure out how to get the mathjax to work inside of a spoiler tag. D:<
    – Frpzzd
    Dec 31 '18 at 21:26






  • 1




    @André Also: I've been trying to do 31, but it actually seems to be much harder than any of the previous ones! Looks like you picked just the right number to stop on! XD
    – Frpzzd
    Dec 31 '18 at 21:27






  • 1




    Your answer for 6 is incorrect; that expression comes out to 2. However, adding parentheses around part and another factorial will make it work.
    – user1207177
    Dec 31 '18 at 21:41





















3














1-16 were done as of the time I started this, so I wanted to focus only on 17-30, using answers different from ones that I've already seen. Others will be included if I find solutions that I like.



8:




$8 = sqrt{(2^{0!+1}!!)!! / (sqrt9)!}$




16:




$16 = ((2 + 0 + 1)!)!! / sqrt9 = 20 - 1 - sqrt9$




17:




$17 = (2 + 0! + 1)!! + 9$




18:




$18 = (2^0 + 1) cdot 9 = 2 cdot (0+1)cdot 9 = 2^{0+1} cdot 9$




19:




$19 = 2 cdot 0 + 19$




20:




$20 = 2^0 + 19 = 20! / 19!$




21:




$21 = 20 + 1^9$




22:




$22 = 20 - 1 + sqrt9$




23:




$23 = 20 + 1 cdot sqrt9$




24:




$24 = 2^{0! + 1} cdot (sqrt9)! = 2^{0! + 1}!! cdot sqrt9 = (2+0!+1)!! cdot sqrt9 = ((2 + 0!)! - 1)!! + 9$




25:




$25 = (2 + 0!)! + 19$




26:




$26 = 20 + 1 cdot (sqrt9)!$




27:




$27 = 2^{0! + 1}! + sqrt9$




28: Can't get one different from what I've already seen in other answers. Will maybe try later.



29:




$29 = 20 + 1 cdot 9$




30:




$30 = 2^{0! + 1}! + (sqrt9)!$




I know we're supposed to stop at 30, but I accidentally found this fun one:



32:




$32 = sqrt{20!! / (1 + 9)!}$







share|improve this answer























  • Well, there's a way to construct the number 31 satisfying the rules above (at least if we allow the subfactorial) :)
    – André
    20 hours ago












  • @André do you mean without concatenation?
    – tilper
    20 hours ago










  • Yes, without concatenation! Hint: Try using the "!!! faculty".
    – André
    19 hours ago





















3














I wrote a program to determine all representable numbers between 1 and 1,000,000 following the rules, so this should be a comprehensive list.



0 through 30:




$$0 = 2times0timesleft(1+9right)$$
$$1 = 20-19$$
$$2 = 2+0timesleft(1+9right)$$
$$3 = 2+0+1^{9}$$
$$4 = 2-left(0+1-sqrt{9}right)$$
$$5 = frac{20}{1+sqrt{9}}$$
$$6 = -2-left(0+1-9right)$$
$$7 = 2timesleft(0-1right)+9$$
$$8 = 2times0-left(1-9right)$$
$$9 = 2times0+1times9$$
$$10 = 2-left(0+1-9right)$$
$$11 = 2+0+1times9$$
$$12 = 2+0+1+9$$
$$13 = 20-left(1+left(sqrt{9}right)!right)$$
$$14 = 20-1timesleft(sqrt{9}right)!$$
$$15 = 20+1-left(sqrt{9}right)!$$
$$16 = 2timesleft(0-left(1-9right)right)$$
$$17 = -2+0+19$$
$$18 = 2timesleft(0+1times9right)$$
$$19 = 2times0+19$$
$$20 = 2timesleft(0+1+9right)$$
$$21 = 2+0+19$$
$$22 = 20-left(1-sqrt{9}right)$$
$$23 = 20+1timessqrt{9}$$
$$24 = 20+1+sqrt{9}$$
$$25 = 20-left(1-left(sqrt{9}right)!right)$$
$$26 = 20+1timesleft(sqrt{9}right)!$$
$$27 = left(2+0+1right)times9$$
$$28 = 20-left(1-9right)$$
$$29 = 20+1times9$$
$$30 = 20+1+9$$




31 through 100. Concatenation of expressions (denoted with ||) is only used when necessary. Interestingly enough, 31 is the smallest number that cannot be done without concatenation of expressions, and 75 is the smallest number that cannot be done in general.




$$31 = 2+left(left(0!+1right)||9right)$$
$$32 = sqrt{2^{0+1+9}}$$
$$33 = left(2+0!+1right)!+9$$
$$34 = left(2+0!right)||left(1+sqrt{9}right)$$
$$35 = 20+left(-1+left(sqrt{9}right)!right)!!$$
$$36 = 2timesleft(-0!+19right)$$
$$37 = left(2+0!right)||left(1+left(sqrt{9}right)!right)$$
$$38 = 2timesleft(0+19right)$$
$$39 = 20+19$$
$$40 = 20timesleft(-1+sqrt{9}right)$$
$$41 = left(left(2+0!right)!right)!!-left(1+left(sqrt{9}right)!right)$$
$$42 = left(2+0!right)!timesleft(1+left(sqrt{9}right)!right)$$
$$43 = left(left(2+0!right)!right)!!+1-left(sqrt{9}right)!$$
$$44 = 20+left(1+sqrt{9}right)!$$
$$45 = left(left(2+0!right)!-1right)times9$$
$$46 = 2timesleft(-0!+left(1+sqrt{9}right)!right)$$
$$47 = 2times0-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$48 = 2timesleft(0+left(1+sqrt{9}right)!right)$$
$$49 = 2-left(0+1-left(left(sqrt{9}right)!right)!!right)$$
$$50 = 2timesleft(0!+left(1+sqrt{9}right)!right)$$
$$51 = 2+0+1+left(left(sqrt{9}right)!right)!!$$
$$52 = 2+0!+1+left(left(sqrt{9}right)!right)!!$$
$$53 = left(2+0!right)!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$54 = left(2+0!right)!times1times9$$
$$55 = left(2+0!right)!+1+left(left(sqrt{9}right)!right)!!$$
$$56 = left(left(2+0!right)!right)!!-left(1-9right)$$
$$57 = left(20-1right)timessqrt{9}$$
$$58 = left(left(2+0!right)!right)!!+1+9$$
$$59 = left(left(2+0!right)!-1right)||9$$
$$60 = 20times1timessqrt{9}$$
$$61 = left(2+0!right)!||left(1^{9}right)$$
$$62 = -2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$63 = left(20+1right)timessqrt{9}$$
$$64 = 2^{0+1timesleft(sqrt{9}right)!}$$
$$65 = left(2+0!right)!||left(-1+left(sqrt{9}right)!right)$$
$$66 = 2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$67 = frac{201}{sqrt{9}}$$
$$68 = 20+1timesleft(left(sqrt{9}right)!right)!!$$
$$69 = -2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$70 = left(left(2+0!right)!||1right)+9$$
$$71 = sqrt{2^{0}+left(1+left(sqrt{9}right)!right)!}$$
$$72 = left(2+0!right)timesleft(1+sqrt{9}right)!$$
$$73 = 2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$74 = 2timesleft(left(-0!||1right)+left(left(sqrt{9}right)!right)!!right)$$
$$76 = left(left(2+0!right)!+1right)||left(sqrt{9}right)!$$
$$78 = left(2+0!right)!timesleft(1||sqrt{9}right)$$
$$79 = left(left(2+0!right)!+1right)||9$$
$$80 = 20timesleft(1+sqrt{9}right)$$
$$81 = left(2+0!right)^{1+sqrt{9}}$$
$$83 = left(2+0!+1right)!!||sqrt{9}$$
$$84 = left(2||0!right)timesleft(1+sqrt{9}right)$$
$$85 = -20+left(1+left(sqrt{9}right)!right)!!$$
$$86 = left(2+0!+1right)!!||left(sqrt{9}right)!$$
$$89 = left(2+0!+1right)!!||9$$
$$90 = frac{left(left(2+0!right)!right)!}{-1+9}$$
$$92 = 2timesleft(-0!-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$93 = left(left(2+0!right)||1right)timessqrt{9}$$
$$94 = 2timesleft(0-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$95 = left(left(2+0!right)!right)!!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$96 = 2timesleft(0+1timesleft(left(sqrt{9}right)!right)!!right)$$
$$97 = left(left(2+0!right)!right)!!+1+left(left(sqrt{9}right)!right)!!$$
$$98 = 2timesleft(0+1+left(left(sqrt{9}right)!right)!!right)$$
$$99 = left(left(2+0!right)!+1right)!!-left(sqrt{9}right)!$$
$$100 = 20timesleft(-1+left(sqrt{9}right)!right)$$




The rest of the numbers from 101 to 1,000,000 can be found here.






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  • Nice. I'm curious whether your program finds anything for 28 other than $20 - (1-9)$ and $20 - 1 +9$, etc.
    – tilper
    yesterday





















0














Disagree about 31, does not need concatenation : 29+1+0! = 31






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olivier is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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    30 mins ago











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5 Answers
5






active

oldest

votes








5 Answers
5






active

oldest

votes









active

oldest

votes






active

oldest

votes









4














1




1 = 2^(0*19)




2




2 = 2 + (0*19)




3




3 = 2 + 0!^19




4




4 = 2 ^ (0! + 1 ^ 9)




5




-((2 + 0! + 1) - 9)




6




-((2 + 0 + 1) - 9))




7




-((2 + 0*1 - 9))




8




-((2 - 01) - 9)




9




2*0*1 + 9




10




2*0 + 1 + 9




11




2 + 0*1 + 9




12




2 + 0 + 1 + 9




13




2 + 0! + 1 + 9




14




(2 + 0!)! - 1 + 9




15




(2 + 0 + 1)! + 9




16




(2 + 0!)! + 1 + 9




17




20 - (1 * sqrt(9))




18




(2 + (0 * 1)) * 9




19




20 - 1^9




20




20 * 1^9




21




20 + 1^9




22




2 + 0! + 19




23




20 + 1 * sqrt(9)




24




20 + 1 + sqrt(9)




25




2 || (0! + 1 + sqrt (9))




explained:




Ok, this one needs explanation. The operation for "grouping" is known as concatenation and represented by ||. Basically this means push the digits together: 2 || 0 = 20. However, just like any operation, you can represent either side not by a number but by an equation on its own. So 0! + 1 + sqrt(9) = 5, meaning the above represents 2 || 5, qed.




26




2 || ((0! + 1) * sqrt(9))




27




(2 + 0 + 1) * 9




28




((2 + 0!) || 1) - sqrt(9)




29




(2 + (0 * 1)) || 9




30




20 + 1 + 9







share|improve this answer























  • edited for clarity
    – flashstorm
    Dec 31 '18 at 18:59










  • @flashstorm Um... $3ne 2+0^{19}$
    – Frpzzd
    Dec 31 '18 at 19:13






  • 1




    was missing an !
    – flashstorm
    Dec 31 '18 at 19:19










  • Ding! Fries are done :)
    – flashstorm
    Dec 31 '18 at 19:31
















4














1




1 = 2^(0*19)




2




2 = 2 + (0*19)




3




3 = 2 + 0!^19




4




4 = 2 ^ (0! + 1 ^ 9)




5




-((2 + 0! + 1) - 9)




6




-((2 + 0 + 1) - 9))




7




-((2 + 0*1 - 9))




8




-((2 - 01) - 9)




9




2*0*1 + 9




10




2*0 + 1 + 9




11




2 + 0*1 + 9




12




2 + 0 + 1 + 9




13




2 + 0! + 1 + 9




14




(2 + 0!)! - 1 + 9




15




(2 + 0 + 1)! + 9




16




(2 + 0!)! + 1 + 9




17




20 - (1 * sqrt(9))




18




(2 + (0 * 1)) * 9




19




20 - 1^9




20




20 * 1^9




21




20 + 1^9




22




2 + 0! + 19




23




20 + 1 * sqrt(9)




24




20 + 1 + sqrt(9)




25




2 || (0! + 1 + sqrt (9))




explained:




Ok, this one needs explanation. The operation for "grouping" is known as concatenation and represented by ||. Basically this means push the digits together: 2 || 0 = 20. However, just like any operation, you can represent either side not by a number but by an equation on its own. So 0! + 1 + sqrt(9) = 5, meaning the above represents 2 || 5, qed.




26




2 || ((0! + 1) * sqrt(9))




27




(2 + 0 + 1) * 9




28




((2 + 0!) || 1) - sqrt(9)




29




(2 + (0 * 1)) || 9




30




20 + 1 + 9







share|improve this answer























  • edited for clarity
    – flashstorm
    Dec 31 '18 at 18:59










  • @flashstorm Um... $3ne 2+0^{19}$
    – Frpzzd
    Dec 31 '18 at 19:13






  • 1




    was missing an !
    – flashstorm
    Dec 31 '18 at 19:19










  • Ding! Fries are done :)
    – flashstorm
    Dec 31 '18 at 19:31














4












4








4






1




1 = 2^(0*19)




2




2 = 2 + (0*19)




3




3 = 2 + 0!^19




4




4 = 2 ^ (0! + 1 ^ 9)




5




-((2 + 0! + 1) - 9)




6




-((2 + 0 + 1) - 9))




7




-((2 + 0*1 - 9))




8




-((2 - 01) - 9)




9




2*0*1 + 9




10




2*0 + 1 + 9




11




2 + 0*1 + 9




12




2 + 0 + 1 + 9




13




2 + 0! + 1 + 9




14




(2 + 0!)! - 1 + 9




15




(2 + 0 + 1)! + 9




16




(2 + 0!)! + 1 + 9




17




20 - (1 * sqrt(9))




18




(2 + (0 * 1)) * 9




19




20 - 1^9




20




20 * 1^9




21




20 + 1^9




22




2 + 0! + 19




23




20 + 1 * sqrt(9)




24




20 + 1 + sqrt(9)




25




2 || (0! + 1 + sqrt (9))




explained:




Ok, this one needs explanation. The operation for "grouping" is known as concatenation and represented by ||. Basically this means push the digits together: 2 || 0 = 20. However, just like any operation, you can represent either side not by a number but by an equation on its own. So 0! + 1 + sqrt(9) = 5, meaning the above represents 2 || 5, qed.




26




2 || ((0! + 1) * sqrt(9))




27




(2 + 0 + 1) * 9




28




((2 + 0!) || 1) - sqrt(9)




29




(2 + (0 * 1)) || 9




30




20 + 1 + 9







share|improve this answer














1




1 = 2^(0*19)




2




2 = 2 + (0*19)




3




3 = 2 + 0!^19




4




4 = 2 ^ (0! + 1 ^ 9)




5




-((2 + 0! + 1) - 9)




6




-((2 + 0 + 1) - 9))




7




-((2 + 0*1 - 9))




8




-((2 - 01) - 9)




9




2*0*1 + 9




10




2*0 + 1 + 9




11




2 + 0*1 + 9




12




2 + 0 + 1 + 9




13




2 + 0! + 1 + 9




14




(2 + 0!)! - 1 + 9




15




(2 + 0 + 1)! + 9




16




(2 + 0!)! + 1 + 9




17




20 - (1 * sqrt(9))




18




(2 + (0 * 1)) * 9




19




20 - 1^9




20




20 * 1^9




21




20 + 1^9




22




2 + 0! + 19




23




20 + 1 * sqrt(9)




24




20 + 1 + sqrt(9)




25




2 || (0! + 1 + sqrt (9))




explained:




Ok, this one needs explanation. The operation for "grouping" is known as concatenation and represented by ||. Basically this means push the digits together: 2 || 0 = 20. However, just like any operation, you can represent either side not by a number but by an equation on its own. So 0! + 1 + sqrt(9) = 5, meaning the above represents 2 || 5, qed.




26




2 || ((0! + 1) * sqrt(9))




27




(2 + 0 + 1) * 9




28




((2 + 0!) || 1) - sqrt(9)




29




(2 + (0 * 1)) || 9




30




20 + 1 + 9








share|improve this answer














share|improve this answer



share|improve this answer








edited Dec 31 '18 at 19:39

























answered Dec 31 '18 at 18:40









flashstorm

7729




7729












  • edited for clarity
    – flashstorm
    Dec 31 '18 at 18:59










  • @flashstorm Um... $3ne 2+0^{19}$
    – Frpzzd
    Dec 31 '18 at 19:13






  • 1




    was missing an !
    – flashstorm
    Dec 31 '18 at 19:19










  • Ding! Fries are done :)
    – flashstorm
    Dec 31 '18 at 19:31


















  • edited for clarity
    – flashstorm
    Dec 31 '18 at 18:59










  • @flashstorm Um... $3ne 2+0^{19}$
    – Frpzzd
    Dec 31 '18 at 19:13






  • 1




    was missing an !
    – flashstorm
    Dec 31 '18 at 19:19










  • Ding! Fries are done :)
    – flashstorm
    Dec 31 '18 at 19:31
















edited for clarity
– flashstorm
Dec 31 '18 at 18:59




edited for clarity
– flashstorm
Dec 31 '18 at 18:59












@flashstorm Um... $3ne 2+0^{19}$
– Frpzzd
Dec 31 '18 at 19:13




@flashstorm Um... $3ne 2+0^{19}$
– Frpzzd
Dec 31 '18 at 19:13




1




1




was missing an !
– flashstorm
Dec 31 '18 at 19:19




was missing an !
– flashstorm
Dec 31 '18 at 19:19












Ding! Fries are done :)
– flashstorm
Dec 31 '18 at 19:31




Ding! Fries are done :)
– flashstorm
Dec 31 '18 at 19:31











7















$$1=20-19$$
$$2=2+0cdot 19=20div(1+9)$$
$$3=2cdot 0cdot 1+sqrt{9}=-(2+0+1)!+9$$
$$4=2^{0-1+sqrt{9}}$$
$$5=20div (1+sqrt{9})$$
$$6=(2cdot 0cdot 1+sqrt{9})!$$
$$7=-2-0cdot 1+9$$
$$8=2^{0cdot 1+sqrt{9}}$$
$$9=2cdot 0cdot 1+9$$
$$10=2cdot 0+1+9=20-1-9$$
$$11=2+0cdot 1+9=20-1cdot 9=2^0+1+9$$
$$12=2+0+1+9=20+1-9$$
$$13=2+0!+1+9=2^{0!+1}+9$$
$$14=(2+0!)!-1+9$$
$$15=(2+0+1)!+9$$
$$16=2^{0+1+sqrt{9}}$$
$$17=20-sqrt{1cdot 9}$$
$$18=20+1-sqrt{9}$$
$$19=2cdot 0+19$$
$$20=2^0+19$$
$$21=20+1^9$$
$$22=2cdot (0!+1+9)$$
$$23=20+sqrt{1cdot 9}$$
$$24=2^{0-1+sqrt{9}}!=20+1+sqrt{9}$$
$$25=(2+0!)!+19$$
$$26=2+0+(1+sqrt{9})!$$
$$27=(2+0+1)^{sqrt{9}}$$
$$28=20-1+9$$
$$29=20+1cdot 9=20cdot 1+9$$
$$30=20+1+9$$




DONE!






share|improve this answer























  • All finished now! :D
    – Frpzzd
    Dec 31 '18 at 19:48










  • Great :) But Spoiler-Tags would be nice ;)
    – André
    Dec 31 '18 at 21:23












  • @André Oh, sorry! I can't figure out how to get the mathjax to work inside of a spoiler tag. D:<
    – Frpzzd
    Dec 31 '18 at 21:26






  • 1




    @André Also: I've been trying to do 31, but it actually seems to be much harder than any of the previous ones! Looks like you picked just the right number to stop on! XD
    – Frpzzd
    Dec 31 '18 at 21:27






  • 1




    Your answer for 6 is incorrect; that expression comes out to 2. However, adding parentheses around part and another factorial will make it work.
    – user1207177
    Dec 31 '18 at 21:41


















7















$$1=20-19$$
$$2=2+0cdot 19=20div(1+9)$$
$$3=2cdot 0cdot 1+sqrt{9}=-(2+0+1)!+9$$
$$4=2^{0-1+sqrt{9}}$$
$$5=20div (1+sqrt{9})$$
$$6=(2cdot 0cdot 1+sqrt{9})!$$
$$7=-2-0cdot 1+9$$
$$8=2^{0cdot 1+sqrt{9}}$$
$$9=2cdot 0cdot 1+9$$
$$10=2cdot 0+1+9=20-1-9$$
$$11=2+0cdot 1+9=20-1cdot 9=2^0+1+9$$
$$12=2+0+1+9=20+1-9$$
$$13=2+0!+1+9=2^{0!+1}+9$$
$$14=(2+0!)!-1+9$$
$$15=(2+0+1)!+9$$
$$16=2^{0+1+sqrt{9}}$$
$$17=20-sqrt{1cdot 9}$$
$$18=20+1-sqrt{9}$$
$$19=2cdot 0+19$$
$$20=2^0+19$$
$$21=20+1^9$$
$$22=2cdot (0!+1+9)$$
$$23=20+sqrt{1cdot 9}$$
$$24=2^{0-1+sqrt{9}}!=20+1+sqrt{9}$$
$$25=(2+0!)!+19$$
$$26=2+0+(1+sqrt{9})!$$
$$27=(2+0+1)^{sqrt{9}}$$
$$28=20-1+9$$
$$29=20+1cdot 9=20cdot 1+9$$
$$30=20+1+9$$




DONE!






share|improve this answer























  • All finished now! :D
    – Frpzzd
    Dec 31 '18 at 19:48










  • Great :) But Spoiler-Tags would be nice ;)
    – André
    Dec 31 '18 at 21:23












  • @André Oh, sorry! I can't figure out how to get the mathjax to work inside of a spoiler tag. D:<
    – Frpzzd
    Dec 31 '18 at 21:26






  • 1




    @André Also: I've been trying to do 31, but it actually seems to be much harder than any of the previous ones! Looks like you picked just the right number to stop on! XD
    – Frpzzd
    Dec 31 '18 at 21:27






  • 1




    Your answer for 6 is incorrect; that expression comes out to 2. However, adding parentheses around part and another factorial will make it work.
    – user1207177
    Dec 31 '18 at 21:41
















7












7








7







$$1=20-19$$
$$2=2+0cdot 19=20div(1+9)$$
$$3=2cdot 0cdot 1+sqrt{9}=-(2+0+1)!+9$$
$$4=2^{0-1+sqrt{9}}$$
$$5=20div (1+sqrt{9})$$
$$6=(2cdot 0cdot 1+sqrt{9})!$$
$$7=-2-0cdot 1+9$$
$$8=2^{0cdot 1+sqrt{9}}$$
$$9=2cdot 0cdot 1+9$$
$$10=2cdot 0+1+9=20-1-9$$
$$11=2+0cdot 1+9=20-1cdot 9=2^0+1+9$$
$$12=2+0+1+9=20+1-9$$
$$13=2+0!+1+9=2^{0!+1}+9$$
$$14=(2+0!)!-1+9$$
$$15=(2+0+1)!+9$$
$$16=2^{0+1+sqrt{9}}$$
$$17=20-sqrt{1cdot 9}$$
$$18=20+1-sqrt{9}$$
$$19=2cdot 0+19$$
$$20=2^0+19$$
$$21=20+1^9$$
$$22=2cdot (0!+1+9)$$
$$23=20+sqrt{1cdot 9}$$
$$24=2^{0-1+sqrt{9}}!=20+1+sqrt{9}$$
$$25=(2+0!)!+19$$
$$26=2+0+(1+sqrt{9})!$$
$$27=(2+0+1)^{sqrt{9}}$$
$$28=20-1+9$$
$$29=20+1cdot 9=20cdot 1+9$$
$$30=20+1+9$$




DONE!






share|improve this answer















$$1=20-19$$
$$2=2+0cdot 19=20div(1+9)$$
$$3=2cdot 0cdot 1+sqrt{9}=-(2+0+1)!+9$$
$$4=2^{0-1+sqrt{9}}$$
$$5=20div (1+sqrt{9})$$
$$6=(2cdot 0cdot 1+sqrt{9})!$$
$$7=-2-0cdot 1+9$$
$$8=2^{0cdot 1+sqrt{9}}$$
$$9=2cdot 0cdot 1+9$$
$$10=2cdot 0+1+9=20-1-9$$
$$11=2+0cdot 1+9=20-1cdot 9=2^0+1+9$$
$$12=2+0+1+9=20+1-9$$
$$13=2+0!+1+9=2^{0!+1}+9$$
$$14=(2+0!)!-1+9$$
$$15=(2+0+1)!+9$$
$$16=2^{0+1+sqrt{9}}$$
$$17=20-sqrt{1cdot 9}$$
$$18=20+1-sqrt{9}$$
$$19=2cdot 0+19$$
$$20=2^0+19$$
$$21=20+1^9$$
$$22=2cdot (0!+1+9)$$
$$23=20+sqrt{1cdot 9}$$
$$24=2^{0-1+sqrt{9}}!=20+1+sqrt{9}$$
$$25=(2+0!)!+19$$
$$26=2+0+(1+sqrt{9})!$$
$$27=(2+0+1)^{sqrt{9}}$$
$$28=20-1+9$$
$$29=20+1cdot 9=20cdot 1+9$$
$$30=20+1+9$$




DONE!







share|improve this answer














share|improve this answer



share|improve this answer








edited 2 days ago









Hugh

1,4681617




1,4681617










answered Dec 31 '18 at 19:21









Frpzzd

871120




871120












  • All finished now! :D
    – Frpzzd
    Dec 31 '18 at 19:48










  • Great :) But Spoiler-Tags would be nice ;)
    – André
    Dec 31 '18 at 21:23












  • @André Oh, sorry! I can't figure out how to get the mathjax to work inside of a spoiler tag. D:<
    – Frpzzd
    Dec 31 '18 at 21:26






  • 1




    @André Also: I've been trying to do 31, but it actually seems to be much harder than any of the previous ones! Looks like you picked just the right number to stop on! XD
    – Frpzzd
    Dec 31 '18 at 21:27






  • 1




    Your answer for 6 is incorrect; that expression comes out to 2. However, adding parentheses around part and another factorial will make it work.
    – user1207177
    Dec 31 '18 at 21:41




















  • All finished now! :D
    – Frpzzd
    Dec 31 '18 at 19:48










  • Great :) But Spoiler-Tags would be nice ;)
    – André
    Dec 31 '18 at 21:23












  • @André Oh, sorry! I can't figure out how to get the mathjax to work inside of a spoiler tag. D:<
    – Frpzzd
    Dec 31 '18 at 21:26






  • 1




    @André Also: I've been trying to do 31, but it actually seems to be much harder than any of the previous ones! Looks like you picked just the right number to stop on! XD
    – Frpzzd
    Dec 31 '18 at 21:27






  • 1




    Your answer for 6 is incorrect; that expression comes out to 2. However, adding parentheses around part and another factorial will make it work.
    – user1207177
    Dec 31 '18 at 21:41


















All finished now! :D
– Frpzzd
Dec 31 '18 at 19:48




All finished now! :D
– Frpzzd
Dec 31 '18 at 19:48












Great :) But Spoiler-Tags would be nice ;)
– André
Dec 31 '18 at 21:23






Great :) But Spoiler-Tags would be nice ;)
– André
Dec 31 '18 at 21:23














@André Oh, sorry! I can't figure out how to get the mathjax to work inside of a spoiler tag. D:<
– Frpzzd
Dec 31 '18 at 21:26




@André Oh, sorry! I can't figure out how to get the mathjax to work inside of a spoiler tag. D:<
– Frpzzd
Dec 31 '18 at 21:26




1




1




@André Also: I've been trying to do 31, but it actually seems to be much harder than any of the previous ones! Looks like you picked just the right number to stop on! XD
– Frpzzd
Dec 31 '18 at 21:27




@André Also: I've been trying to do 31, but it actually seems to be much harder than any of the previous ones! Looks like you picked just the right number to stop on! XD
– Frpzzd
Dec 31 '18 at 21:27




1




1




Your answer for 6 is incorrect; that expression comes out to 2. However, adding parentheses around part and another factorial will make it work.
– user1207177
Dec 31 '18 at 21:41






Your answer for 6 is incorrect; that expression comes out to 2. However, adding parentheses around part and another factorial will make it work.
– user1207177
Dec 31 '18 at 21:41













3














1-16 were done as of the time I started this, so I wanted to focus only on 17-30, using answers different from ones that I've already seen. Others will be included if I find solutions that I like.



8:




$8 = sqrt{(2^{0!+1}!!)!! / (sqrt9)!}$




16:




$16 = ((2 + 0 + 1)!)!! / sqrt9 = 20 - 1 - sqrt9$




17:




$17 = (2 + 0! + 1)!! + 9$




18:




$18 = (2^0 + 1) cdot 9 = 2 cdot (0+1)cdot 9 = 2^{0+1} cdot 9$




19:




$19 = 2 cdot 0 + 19$




20:




$20 = 2^0 + 19 = 20! / 19!$




21:




$21 = 20 + 1^9$




22:




$22 = 20 - 1 + sqrt9$




23:




$23 = 20 + 1 cdot sqrt9$




24:




$24 = 2^{0! + 1} cdot (sqrt9)! = 2^{0! + 1}!! cdot sqrt9 = (2+0!+1)!! cdot sqrt9 = ((2 + 0!)! - 1)!! + 9$




25:




$25 = (2 + 0!)! + 19$




26:




$26 = 20 + 1 cdot (sqrt9)!$




27:




$27 = 2^{0! + 1}! + sqrt9$




28: Can't get one different from what I've already seen in other answers. Will maybe try later.



29:




$29 = 20 + 1 cdot 9$




30:




$30 = 2^{0! + 1}! + (sqrt9)!$




I know we're supposed to stop at 30, but I accidentally found this fun one:



32:




$32 = sqrt{20!! / (1 + 9)!}$







share|improve this answer























  • Well, there's a way to construct the number 31 satisfying the rules above (at least if we allow the subfactorial) :)
    – André
    20 hours ago












  • @André do you mean without concatenation?
    – tilper
    20 hours ago










  • Yes, without concatenation! Hint: Try using the "!!! faculty".
    – André
    19 hours ago


















3














1-16 were done as of the time I started this, so I wanted to focus only on 17-30, using answers different from ones that I've already seen. Others will be included if I find solutions that I like.



8:




$8 = sqrt{(2^{0!+1}!!)!! / (sqrt9)!}$




16:




$16 = ((2 + 0 + 1)!)!! / sqrt9 = 20 - 1 - sqrt9$




17:




$17 = (2 + 0! + 1)!! + 9$




18:




$18 = (2^0 + 1) cdot 9 = 2 cdot (0+1)cdot 9 = 2^{0+1} cdot 9$




19:




$19 = 2 cdot 0 + 19$




20:




$20 = 2^0 + 19 = 20! / 19!$




21:




$21 = 20 + 1^9$




22:




$22 = 20 - 1 + sqrt9$




23:




$23 = 20 + 1 cdot sqrt9$




24:




$24 = 2^{0! + 1} cdot (sqrt9)! = 2^{0! + 1}!! cdot sqrt9 = (2+0!+1)!! cdot sqrt9 = ((2 + 0!)! - 1)!! + 9$




25:




$25 = (2 + 0!)! + 19$




26:




$26 = 20 + 1 cdot (sqrt9)!$




27:




$27 = 2^{0! + 1}! + sqrt9$




28: Can't get one different from what I've already seen in other answers. Will maybe try later.



29:




$29 = 20 + 1 cdot 9$




30:




$30 = 2^{0! + 1}! + (sqrt9)!$




I know we're supposed to stop at 30, but I accidentally found this fun one:



32:




$32 = sqrt{20!! / (1 + 9)!}$







share|improve this answer























  • Well, there's a way to construct the number 31 satisfying the rules above (at least if we allow the subfactorial) :)
    – André
    20 hours ago












  • @André do you mean without concatenation?
    – tilper
    20 hours ago










  • Yes, without concatenation! Hint: Try using the "!!! faculty".
    – André
    19 hours ago
















3












3








3






1-16 were done as of the time I started this, so I wanted to focus only on 17-30, using answers different from ones that I've already seen. Others will be included if I find solutions that I like.



8:




$8 = sqrt{(2^{0!+1}!!)!! / (sqrt9)!}$




16:




$16 = ((2 + 0 + 1)!)!! / sqrt9 = 20 - 1 - sqrt9$




17:




$17 = (2 + 0! + 1)!! + 9$




18:




$18 = (2^0 + 1) cdot 9 = 2 cdot (0+1)cdot 9 = 2^{0+1} cdot 9$




19:




$19 = 2 cdot 0 + 19$




20:




$20 = 2^0 + 19 = 20! / 19!$




21:




$21 = 20 + 1^9$




22:




$22 = 20 - 1 + sqrt9$




23:




$23 = 20 + 1 cdot sqrt9$




24:




$24 = 2^{0! + 1} cdot (sqrt9)! = 2^{0! + 1}!! cdot sqrt9 = (2+0!+1)!! cdot sqrt9 = ((2 + 0!)! - 1)!! + 9$




25:




$25 = (2 + 0!)! + 19$




26:




$26 = 20 + 1 cdot (sqrt9)!$




27:




$27 = 2^{0! + 1}! + sqrt9$




28: Can't get one different from what I've already seen in other answers. Will maybe try later.



29:




$29 = 20 + 1 cdot 9$




30:




$30 = 2^{0! + 1}! + (sqrt9)!$




I know we're supposed to stop at 30, but I accidentally found this fun one:



32:




$32 = sqrt{20!! / (1 + 9)!}$







share|improve this answer














1-16 were done as of the time I started this, so I wanted to focus only on 17-30, using answers different from ones that I've already seen. Others will be included if I find solutions that I like.



8:




$8 = sqrt{(2^{0!+1}!!)!! / (sqrt9)!}$




16:




$16 = ((2 + 0 + 1)!)!! / sqrt9 = 20 - 1 - sqrt9$




17:




$17 = (2 + 0! + 1)!! + 9$




18:




$18 = (2^0 + 1) cdot 9 = 2 cdot (0+1)cdot 9 = 2^{0+1} cdot 9$




19:




$19 = 2 cdot 0 + 19$




20:




$20 = 2^0 + 19 = 20! / 19!$




21:




$21 = 20 + 1^9$




22:




$22 = 20 - 1 + sqrt9$




23:




$23 = 20 + 1 cdot sqrt9$




24:




$24 = 2^{0! + 1} cdot (sqrt9)! = 2^{0! + 1}!! cdot sqrt9 = (2+0!+1)!! cdot sqrt9 = ((2 + 0!)! - 1)!! + 9$




25:




$25 = (2 + 0!)! + 19$




26:




$26 = 20 + 1 cdot (sqrt9)!$




27:




$27 = 2^{0! + 1}! + sqrt9$




28: Can't get one different from what I've already seen in other answers. Will maybe try later.



29:




$29 = 20 + 1 cdot 9$




30:




$30 = 2^{0! + 1}! + (sqrt9)!$




I know we're supposed to stop at 30, but I accidentally found this fun one:



32:




$32 = sqrt{20!! / (1 + 9)!}$








share|improve this answer














share|improve this answer



share|improve this answer








edited Dec 31 '18 at 20:48

























answered Dec 31 '18 at 19:13









tilper

892514




892514












  • Well, there's a way to construct the number 31 satisfying the rules above (at least if we allow the subfactorial) :)
    – André
    20 hours ago












  • @André do you mean without concatenation?
    – tilper
    20 hours ago










  • Yes, without concatenation! Hint: Try using the "!!! faculty".
    – André
    19 hours ago




















  • Well, there's a way to construct the number 31 satisfying the rules above (at least if we allow the subfactorial) :)
    – André
    20 hours ago












  • @André do you mean without concatenation?
    – tilper
    20 hours ago










  • Yes, without concatenation! Hint: Try using the "!!! faculty".
    – André
    19 hours ago


















Well, there's a way to construct the number 31 satisfying the rules above (at least if we allow the subfactorial) :)
– André
20 hours ago






Well, there's a way to construct the number 31 satisfying the rules above (at least if we allow the subfactorial) :)
– André
20 hours ago














@André do you mean without concatenation?
– tilper
20 hours ago




@André do you mean without concatenation?
– tilper
20 hours ago












Yes, without concatenation! Hint: Try using the "!!! faculty".
– André
19 hours ago






Yes, without concatenation! Hint: Try using the "!!! faculty".
– André
19 hours ago













3














I wrote a program to determine all representable numbers between 1 and 1,000,000 following the rules, so this should be a comprehensive list.



0 through 30:




$$0 = 2times0timesleft(1+9right)$$
$$1 = 20-19$$
$$2 = 2+0timesleft(1+9right)$$
$$3 = 2+0+1^{9}$$
$$4 = 2-left(0+1-sqrt{9}right)$$
$$5 = frac{20}{1+sqrt{9}}$$
$$6 = -2-left(0+1-9right)$$
$$7 = 2timesleft(0-1right)+9$$
$$8 = 2times0-left(1-9right)$$
$$9 = 2times0+1times9$$
$$10 = 2-left(0+1-9right)$$
$$11 = 2+0+1times9$$
$$12 = 2+0+1+9$$
$$13 = 20-left(1+left(sqrt{9}right)!right)$$
$$14 = 20-1timesleft(sqrt{9}right)!$$
$$15 = 20+1-left(sqrt{9}right)!$$
$$16 = 2timesleft(0-left(1-9right)right)$$
$$17 = -2+0+19$$
$$18 = 2timesleft(0+1times9right)$$
$$19 = 2times0+19$$
$$20 = 2timesleft(0+1+9right)$$
$$21 = 2+0+19$$
$$22 = 20-left(1-sqrt{9}right)$$
$$23 = 20+1timessqrt{9}$$
$$24 = 20+1+sqrt{9}$$
$$25 = 20-left(1-left(sqrt{9}right)!right)$$
$$26 = 20+1timesleft(sqrt{9}right)!$$
$$27 = left(2+0+1right)times9$$
$$28 = 20-left(1-9right)$$
$$29 = 20+1times9$$
$$30 = 20+1+9$$




31 through 100. Concatenation of expressions (denoted with ||) is only used when necessary. Interestingly enough, 31 is the smallest number that cannot be done without concatenation of expressions, and 75 is the smallest number that cannot be done in general.




$$31 = 2+left(left(0!+1right)||9right)$$
$$32 = sqrt{2^{0+1+9}}$$
$$33 = left(2+0!+1right)!+9$$
$$34 = left(2+0!right)||left(1+sqrt{9}right)$$
$$35 = 20+left(-1+left(sqrt{9}right)!right)!!$$
$$36 = 2timesleft(-0!+19right)$$
$$37 = left(2+0!right)||left(1+left(sqrt{9}right)!right)$$
$$38 = 2timesleft(0+19right)$$
$$39 = 20+19$$
$$40 = 20timesleft(-1+sqrt{9}right)$$
$$41 = left(left(2+0!right)!right)!!-left(1+left(sqrt{9}right)!right)$$
$$42 = left(2+0!right)!timesleft(1+left(sqrt{9}right)!right)$$
$$43 = left(left(2+0!right)!right)!!+1-left(sqrt{9}right)!$$
$$44 = 20+left(1+sqrt{9}right)!$$
$$45 = left(left(2+0!right)!-1right)times9$$
$$46 = 2timesleft(-0!+left(1+sqrt{9}right)!right)$$
$$47 = 2times0-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$48 = 2timesleft(0+left(1+sqrt{9}right)!right)$$
$$49 = 2-left(0+1-left(left(sqrt{9}right)!right)!!right)$$
$$50 = 2timesleft(0!+left(1+sqrt{9}right)!right)$$
$$51 = 2+0+1+left(left(sqrt{9}right)!right)!!$$
$$52 = 2+0!+1+left(left(sqrt{9}right)!right)!!$$
$$53 = left(2+0!right)!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$54 = left(2+0!right)!times1times9$$
$$55 = left(2+0!right)!+1+left(left(sqrt{9}right)!right)!!$$
$$56 = left(left(2+0!right)!right)!!-left(1-9right)$$
$$57 = left(20-1right)timessqrt{9}$$
$$58 = left(left(2+0!right)!right)!!+1+9$$
$$59 = left(left(2+0!right)!-1right)||9$$
$$60 = 20times1timessqrt{9}$$
$$61 = left(2+0!right)!||left(1^{9}right)$$
$$62 = -2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$63 = left(20+1right)timessqrt{9}$$
$$64 = 2^{0+1timesleft(sqrt{9}right)!}$$
$$65 = left(2+0!right)!||left(-1+left(sqrt{9}right)!right)$$
$$66 = 2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$67 = frac{201}{sqrt{9}}$$
$$68 = 20+1timesleft(left(sqrt{9}right)!right)!!$$
$$69 = -2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$70 = left(left(2+0!right)!||1right)+9$$
$$71 = sqrt{2^{0}+left(1+left(sqrt{9}right)!right)!}$$
$$72 = left(2+0!right)timesleft(1+sqrt{9}right)!$$
$$73 = 2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$74 = 2timesleft(left(-0!||1right)+left(left(sqrt{9}right)!right)!!right)$$
$$76 = left(left(2+0!right)!+1right)||left(sqrt{9}right)!$$
$$78 = left(2+0!right)!timesleft(1||sqrt{9}right)$$
$$79 = left(left(2+0!right)!+1right)||9$$
$$80 = 20timesleft(1+sqrt{9}right)$$
$$81 = left(2+0!right)^{1+sqrt{9}}$$
$$83 = left(2+0!+1right)!!||sqrt{9}$$
$$84 = left(2||0!right)timesleft(1+sqrt{9}right)$$
$$85 = -20+left(1+left(sqrt{9}right)!right)!!$$
$$86 = left(2+0!+1right)!!||left(sqrt{9}right)!$$
$$89 = left(2+0!+1right)!!||9$$
$$90 = frac{left(left(2+0!right)!right)!}{-1+9}$$
$$92 = 2timesleft(-0!-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$93 = left(left(2+0!right)||1right)timessqrt{9}$$
$$94 = 2timesleft(0-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$95 = left(left(2+0!right)!right)!!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$96 = 2timesleft(0+1timesleft(left(sqrt{9}right)!right)!!right)$$
$$97 = left(left(2+0!right)!right)!!+1+left(left(sqrt{9}right)!right)!!$$
$$98 = 2timesleft(0+1+left(left(sqrt{9}right)!right)!!right)$$
$$99 = left(left(2+0!right)!+1right)!!-left(sqrt{9}right)!$$
$$100 = 20timesleft(-1+left(sqrt{9}right)!right)$$




The rest of the numbers from 101 to 1,000,000 can be found here.






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  • Nice. I'm curious whether your program finds anything for 28 other than $20 - (1-9)$ and $20 - 1 +9$, etc.
    – tilper
    yesterday


















3














I wrote a program to determine all representable numbers between 1 and 1,000,000 following the rules, so this should be a comprehensive list.



0 through 30:




$$0 = 2times0timesleft(1+9right)$$
$$1 = 20-19$$
$$2 = 2+0timesleft(1+9right)$$
$$3 = 2+0+1^{9}$$
$$4 = 2-left(0+1-sqrt{9}right)$$
$$5 = frac{20}{1+sqrt{9}}$$
$$6 = -2-left(0+1-9right)$$
$$7 = 2timesleft(0-1right)+9$$
$$8 = 2times0-left(1-9right)$$
$$9 = 2times0+1times9$$
$$10 = 2-left(0+1-9right)$$
$$11 = 2+0+1times9$$
$$12 = 2+0+1+9$$
$$13 = 20-left(1+left(sqrt{9}right)!right)$$
$$14 = 20-1timesleft(sqrt{9}right)!$$
$$15 = 20+1-left(sqrt{9}right)!$$
$$16 = 2timesleft(0-left(1-9right)right)$$
$$17 = -2+0+19$$
$$18 = 2timesleft(0+1times9right)$$
$$19 = 2times0+19$$
$$20 = 2timesleft(0+1+9right)$$
$$21 = 2+0+19$$
$$22 = 20-left(1-sqrt{9}right)$$
$$23 = 20+1timessqrt{9}$$
$$24 = 20+1+sqrt{9}$$
$$25 = 20-left(1-left(sqrt{9}right)!right)$$
$$26 = 20+1timesleft(sqrt{9}right)!$$
$$27 = left(2+0+1right)times9$$
$$28 = 20-left(1-9right)$$
$$29 = 20+1times9$$
$$30 = 20+1+9$$




31 through 100. Concatenation of expressions (denoted with ||) is only used when necessary. Interestingly enough, 31 is the smallest number that cannot be done without concatenation of expressions, and 75 is the smallest number that cannot be done in general.




$$31 = 2+left(left(0!+1right)||9right)$$
$$32 = sqrt{2^{0+1+9}}$$
$$33 = left(2+0!+1right)!+9$$
$$34 = left(2+0!right)||left(1+sqrt{9}right)$$
$$35 = 20+left(-1+left(sqrt{9}right)!right)!!$$
$$36 = 2timesleft(-0!+19right)$$
$$37 = left(2+0!right)||left(1+left(sqrt{9}right)!right)$$
$$38 = 2timesleft(0+19right)$$
$$39 = 20+19$$
$$40 = 20timesleft(-1+sqrt{9}right)$$
$$41 = left(left(2+0!right)!right)!!-left(1+left(sqrt{9}right)!right)$$
$$42 = left(2+0!right)!timesleft(1+left(sqrt{9}right)!right)$$
$$43 = left(left(2+0!right)!right)!!+1-left(sqrt{9}right)!$$
$$44 = 20+left(1+sqrt{9}right)!$$
$$45 = left(left(2+0!right)!-1right)times9$$
$$46 = 2timesleft(-0!+left(1+sqrt{9}right)!right)$$
$$47 = 2times0-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$48 = 2timesleft(0+left(1+sqrt{9}right)!right)$$
$$49 = 2-left(0+1-left(left(sqrt{9}right)!right)!!right)$$
$$50 = 2timesleft(0!+left(1+sqrt{9}right)!right)$$
$$51 = 2+0+1+left(left(sqrt{9}right)!right)!!$$
$$52 = 2+0!+1+left(left(sqrt{9}right)!right)!!$$
$$53 = left(2+0!right)!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$54 = left(2+0!right)!times1times9$$
$$55 = left(2+0!right)!+1+left(left(sqrt{9}right)!right)!!$$
$$56 = left(left(2+0!right)!right)!!-left(1-9right)$$
$$57 = left(20-1right)timessqrt{9}$$
$$58 = left(left(2+0!right)!right)!!+1+9$$
$$59 = left(left(2+0!right)!-1right)||9$$
$$60 = 20times1timessqrt{9}$$
$$61 = left(2+0!right)!||left(1^{9}right)$$
$$62 = -2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$63 = left(20+1right)timessqrt{9}$$
$$64 = 2^{0+1timesleft(sqrt{9}right)!}$$
$$65 = left(2+0!right)!||left(-1+left(sqrt{9}right)!right)$$
$$66 = 2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$67 = frac{201}{sqrt{9}}$$
$$68 = 20+1timesleft(left(sqrt{9}right)!right)!!$$
$$69 = -2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$70 = left(left(2+0!right)!||1right)+9$$
$$71 = sqrt{2^{0}+left(1+left(sqrt{9}right)!right)!}$$
$$72 = left(2+0!right)timesleft(1+sqrt{9}right)!$$
$$73 = 2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$74 = 2timesleft(left(-0!||1right)+left(left(sqrt{9}right)!right)!!right)$$
$$76 = left(left(2+0!right)!+1right)||left(sqrt{9}right)!$$
$$78 = left(2+0!right)!timesleft(1||sqrt{9}right)$$
$$79 = left(left(2+0!right)!+1right)||9$$
$$80 = 20timesleft(1+sqrt{9}right)$$
$$81 = left(2+0!right)^{1+sqrt{9}}$$
$$83 = left(2+0!+1right)!!||sqrt{9}$$
$$84 = left(2||0!right)timesleft(1+sqrt{9}right)$$
$$85 = -20+left(1+left(sqrt{9}right)!right)!!$$
$$86 = left(2+0!+1right)!!||left(sqrt{9}right)!$$
$$89 = left(2+0!+1right)!!||9$$
$$90 = frac{left(left(2+0!right)!right)!}{-1+9}$$
$$92 = 2timesleft(-0!-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$93 = left(left(2+0!right)||1right)timessqrt{9}$$
$$94 = 2timesleft(0-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$95 = left(left(2+0!right)!right)!!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$96 = 2timesleft(0+1timesleft(left(sqrt{9}right)!right)!!right)$$
$$97 = left(left(2+0!right)!right)!!+1+left(left(sqrt{9}right)!right)!!$$
$$98 = 2timesleft(0+1+left(left(sqrt{9}right)!right)!!right)$$
$$99 = left(left(2+0!right)!+1right)!!-left(sqrt{9}right)!$$
$$100 = 20timesleft(-1+left(sqrt{9}right)!right)$$




The rest of the numbers from 101 to 1,000,000 can be found here.






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  • Nice. I'm curious whether your program finds anything for 28 other than $20 - (1-9)$ and $20 - 1 +9$, etc.
    – tilper
    yesterday
















3












3








3






I wrote a program to determine all representable numbers between 1 and 1,000,000 following the rules, so this should be a comprehensive list.



0 through 30:




$$0 = 2times0timesleft(1+9right)$$
$$1 = 20-19$$
$$2 = 2+0timesleft(1+9right)$$
$$3 = 2+0+1^{9}$$
$$4 = 2-left(0+1-sqrt{9}right)$$
$$5 = frac{20}{1+sqrt{9}}$$
$$6 = -2-left(0+1-9right)$$
$$7 = 2timesleft(0-1right)+9$$
$$8 = 2times0-left(1-9right)$$
$$9 = 2times0+1times9$$
$$10 = 2-left(0+1-9right)$$
$$11 = 2+0+1times9$$
$$12 = 2+0+1+9$$
$$13 = 20-left(1+left(sqrt{9}right)!right)$$
$$14 = 20-1timesleft(sqrt{9}right)!$$
$$15 = 20+1-left(sqrt{9}right)!$$
$$16 = 2timesleft(0-left(1-9right)right)$$
$$17 = -2+0+19$$
$$18 = 2timesleft(0+1times9right)$$
$$19 = 2times0+19$$
$$20 = 2timesleft(0+1+9right)$$
$$21 = 2+0+19$$
$$22 = 20-left(1-sqrt{9}right)$$
$$23 = 20+1timessqrt{9}$$
$$24 = 20+1+sqrt{9}$$
$$25 = 20-left(1-left(sqrt{9}right)!right)$$
$$26 = 20+1timesleft(sqrt{9}right)!$$
$$27 = left(2+0+1right)times9$$
$$28 = 20-left(1-9right)$$
$$29 = 20+1times9$$
$$30 = 20+1+9$$




31 through 100. Concatenation of expressions (denoted with ||) is only used when necessary. Interestingly enough, 31 is the smallest number that cannot be done without concatenation of expressions, and 75 is the smallest number that cannot be done in general.




$$31 = 2+left(left(0!+1right)||9right)$$
$$32 = sqrt{2^{0+1+9}}$$
$$33 = left(2+0!+1right)!+9$$
$$34 = left(2+0!right)||left(1+sqrt{9}right)$$
$$35 = 20+left(-1+left(sqrt{9}right)!right)!!$$
$$36 = 2timesleft(-0!+19right)$$
$$37 = left(2+0!right)||left(1+left(sqrt{9}right)!right)$$
$$38 = 2timesleft(0+19right)$$
$$39 = 20+19$$
$$40 = 20timesleft(-1+sqrt{9}right)$$
$$41 = left(left(2+0!right)!right)!!-left(1+left(sqrt{9}right)!right)$$
$$42 = left(2+0!right)!timesleft(1+left(sqrt{9}right)!right)$$
$$43 = left(left(2+0!right)!right)!!+1-left(sqrt{9}right)!$$
$$44 = 20+left(1+sqrt{9}right)!$$
$$45 = left(left(2+0!right)!-1right)times9$$
$$46 = 2timesleft(-0!+left(1+sqrt{9}right)!right)$$
$$47 = 2times0-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$48 = 2timesleft(0+left(1+sqrt{9}right)!right)$$
$$49 = 2-left(0+1-left(left(sqrt{9}right)!right)!!right)$$
$$50 = 2timesleft(0!+left(1+sqrt{9}right)!right)$$
$$51 = 2+0+1+left(left(sqrt{9}right)!right)!!$$
$$52 = 2+0!+1+left(left(sqrt{9}right)!right)!!$$
$$53 = left(2+0!right)!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$54 = left(2+0!right)!times1times9$$
$$55 = left(2+0!right)!+1+left(left(sqrt{9}right)!right)!!$$
$$56 = left(left(2+0!right)!right)!!-left(1-9right)$$
$$57 = left(20-1right)timessqrt{9}$$
$$58 = left(left(2+0!right)!right)!!+1+9$$
$$59 = left(left(2+0!right)!-1right)||9$$
$$60 = 20times1timessqrt{9}$$
$$61 = left(2+0!right)!||left(1^{9}right)$$
$$62 = -2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$63 = left(20+1right)timessqrt{9}$$
$$64 = 2^{0+1timesleft(sqrt{9}right)!}$$
$$65 = left(2+0!right)!||left(-1+left(sqrt{9}right)!right)$$
$$66 = 2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$67 = frac{201}{sqrt{9}}$$
$$68 = 20+1timesleft(left(sqrt{9}right)!right)!!$$
$$69 = -2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$70 = left(left(2+0!right)!||1right)+9$$
$$71 = sqrt{2^{0}+left(1+left(sqrt{9}right)!right)!}$$
$$72 = left(2+0!right)timesleft(1+sqrt{9}right)!$$
$$73 = 2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$74 = 2timesleft(left(-0!||1right)+left(left(sqrt{9}right)!right)!!right)$$
$$76 = left(left(2+0!right)!+1right)||left(sqrt{9}right)!$$
$$78 = left(2+0!right)!timesleft(1||sqrt{9}right)$$
$$79 = left(left(2+0!right)!+1right)||9$$
$$80 = 20timesleft(1+sqrt{9}right)$$
$$81 = left(2+0!right)^{1+sqrt{9}}$$
$$83 = left(2+0!+1right)!!||sqrt{9}$$
$$84 = left(2||0!right)timesleft(1+sqrt{9}right)$$
$$85 = -20+left(1+left(sqrt{9}right)!right)!!$$
$$86 = left(2+0!+1right)!!||left(sqrt{9}right)!$$
$$89 = left(2+0!+1right)!!||9$$
$$90 = frac{left(left(2+0!right)!right)!}{-1+9}$$
$$92 = 2timesleft(-0!-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$93 = left(left(2+0!right)||1right)timessqrt{9}$$
$$94 = 2timesleft(0-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$95 = left(left(2+0!right)!right)!!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$96 = 2timesleft(0+1timesleft(left(sqrt{9}right)!right)!!right)$$
$$97 = left(left(2+0!right)!right)!!+1+left(left(sqrt{9}right)!right)!!$$
$$98 = 2timesleft(0+1+left(left(sqrt{9}right)!right)!!right)$$
$$99 = left(left(2+0!right)!+1right)!!-left(sqrt{9}right)!$$
$$100 = 20timesleft(-1+left(sqrt{9}right)!right)$$




The rest of the numbers from 101 to 1,000,000 can be found here.






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I wrote a program to determine all representable numbers between 1 and 1,000,000 following the rules, so this should be a comprehensive list.



0 through 30:




$$0 = 2times0timesleft(1+9right)$$
$$1 = 20-19$$
$$2 = 2+0timesleft(1+9right)$$
$$3 = 2+0+1^{9}$$
$$4 = 2-left(0+1-sqrt{9}right)$$
$$5 = frac{20}{1+sqrt{9}}$$
$$6 = -2-left(0+1-9right)$$
$$7 = 2timesleft(0-1right)+9$$
$$8 = 2times0-left(1-9right)$$
$$9 = 2times0+1times9$$
$$10 = 2-left(0+1-9right)$$
$$11 = 2+0+1times9$$
$$12 = 2+0+1+9$$
$$13 = 20-left(1+left(sqrt{9}right)!right)$$
$$14 = 20-1timesleft(sqrt{9}right)!$$
$$15 = 20+1-left(sqrt{9}right)!$$
$$16 = 2timesleft(0-left(1-9right)right)$$
$$17 = -2+0+19$$
$$18 = 2timesleft(0+1times9right)$$
$$19 = 2times0+19$$
$$20 = 2timesleft(0+1+9right)$$
$$21 = 2+0+19$$
$$22 = 20-left(1-sqrt{9}right)$$
$$23 = 20+1timessqrt{9}$$
$$24 = 20+1+sqrt{9}$$
$$25 = 20-left(1-left(sqrt{9}right)!right)$$
$$26 = 20+1timesleft(sqrt{9}right)!$$
$$27 = left(2+0+1right)times9$$
$$28 = 20-left(1-9right)$$
$$29 = 20+1times9$$
$$30 = 20+1+9$$




31 through 100. Concatenation of expressions (denoted with ||) is only used when necessary. Interestingly enough, 31 is the smallest number that cannot be done without concatenation of expressions, and 75 is the smallest number that cannot be done in general.




$$31 = 2+left(left(0!+1right)||9right)$$
$$32 = sqrt{2^{0+1+9}}$$
$$33 = left(2+0!+1right)!+9$$
$$34 = left(2+0!right)||left(1+sqrt{9}right)$$
$$35 = 20+left(-1+left(sqrt{9}right)!right)!!$$
$$36 = 2timesleft(-0!+19right)$$
$$37 = left(2+0!right)||left(1+left(sqrt{9}right)!right)$$
$$38 = 2timesleft(0+19right)$$
$$39 = 20+19$$
$$40 = 20timesleft(-1+sqrt{9}right)$$
$$41 = left(left(2+0!right)!right)!!-left(1+left(sqrt{9}right)!right)$$
$$42 = left(2+0!right)!timesleft(1+left(sqrt{9}right)!right)$$
$$43 = left(left(2+0!right)!right)!!+1-left(sqrt{9}right)!$$
$$44 = 20+left(1+sqrt{9}right)!$$
$$45 = left(left(2+0!right)!-1right)times9$$
$$46 = 2timesleft(-0!+left(1+sqrt{9}right)!right)$$
$$47 = 2times0-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$48 = 2timesleft(0+left(1+sqrt{9}right)!right)$$
$$49 = 2-left(0+1-left(left(sqrt{9}right)!right)!!right)$$
$$50 = 2timesleft(0!+left(1+sqrt{9}right)!right)$$
$$51 = 2+0+1+left(left(sqrt{9}right)!right)!!$$
$$52 = 2+0!+1+left(left(sqrt{9}right)!right)!!$$
$$53 = left(2+0!right)!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$54 = left(2+0!right)!times1times9$$
$$55 = left(2+0!right)!+1+left(left(sqrt{9}right)!right)!!$$
$$56 = left(left(2+0!right)!right)!!-left(1-9right)$$
$$57 = left(20-1right)timessqrt{9}$$
$$58 = left(left(2+0!right)!right)!!+1+9$$
$$59 = left(left(2+0!right)!-1right)||9$$
$$60 = 20times1timessqrt{9}$$
$$61 = left(2+0!right)!||left(1^{9}right)$$
$$62 = -2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$63 = left(20+1right)timessqrt{9}$$
$$64 = 2^{0+1timesleft(sqrt{9}right)!}$$
$$65 = left(2+0!right)!||left(-1+left(sqrt{9}right)!right)$$
$$66 = 2+left(0!+1right)^{left(sqrt{9}right)!}$$
$$67 = frac{201}{sqrt{9}}$$
$$68 = 20+1timesleft(left(sqrt{9}right)!right)!!$$
$$69 = -2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$70 = left(left(2+0!right)!||1right)+9$$
$$71 = sqrt{2^{0}+left(1+left(sqrt{9}right)!right)!}$$
$$72 = left(2+0!right)timesleft(1+sqrt{9}right)!$$
$$73 = 2+sqrt{0!+left(1+left(sqrt{9}right)!right)!}$$
$$74 = 2timesleft(left(-0!||1right)+left(left(sqrt{9}right)!right)!!right)$$
$$76 = left(left(2+0!right)!+1right)||left(sqrt{9}right)!$$
$$78 = left(2+0!right)!timesleft(1||sqrt{9}right)$$
$$79 = left(left(2+0!right)!+1right)||9$$
$$80 = 20timesleft(1+sqrt{9}right)$$
$$81 = left(2+0!right)^{1+sqrt{9}}$$
$$83 = left(2+0!+1right)!!||sqrt{9}$$
$$84 = left(2||0!right)timesleft(1+sqrt{9}right)$$
$$85 = -20+left(1+left(sqrt{9}right)!right)!!$$
$$86 = left(2+0!+1right)!!||left(sqrt{9}right)!$$
$$89 = left(2+0!+1right)!!||9$$
$$90 = frac{left(left(2+0!right)!right)!}{-1+9}$$
$$92 = 2timesleft(-0!-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$93 = left(left(2+0!right)||1right)timessqrt{9}$$
$$94 = 2timesleft(0-left(1-left(left(sqrt{9}right)!right)!!right)right)$$
$$95 = left(left(2+0!right)!right)!!-left(1-left(left(sqrt{9}right)!right)!!right)$$
$$96 = 2timesleft(0+1timesleft(left(sqrt{9}right)!right)!!right)$$
$$97 = left(left(2+0!right)!right)!!+1+left(left(sqrt{9}right)!right)!!$$
$$98 = 2timesleft(0+1+left(left(sqrt{9}right)!right)!!right)$$
$$99 = left(left(2+0!right)!+1right)!!-left(sqrt{9}right)!$$
$$100 = 20timesleft(-1+left(sqrt{9}right)!right)$$




The rest of the numbers from 101 to 1,000,000 can be found here.







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edited 2 days ago





















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answered 2 days ago









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  • Nice. I'm curious whether your program finds anything for 28 other than $20 - (1-9)$ and $20 - 1 +9$, etc.
    – tilper
    yesterday




















  • Nice. I'm curious whether your program finds anything for 28 other than $20 - (1-9)$ and $20 - 1 +9$, etc.
    – tilper
    yesterday


















Nice. I'm curious whether your program finds anything for 28 other than $20 - (1-9)$ and $20 - 1 +9$, etc.
– tilper
yesterday






Nice. I'm curious whether your program finds anything for 28 other than $20 - (1-9)$ and $20 - 1 +9$, etc.
– tilper
yesterday













0














Disagree about 31, does not need concatenation : 29+1+0! = 31






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0














Disagree about 31, does not need concatenation : 29+1+0! = 31






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  • This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
    – A. P.
    30 mins ago














0












0








0






Disagree about 31, does not need concatenation : 29+1+0! = 31






share|improve this answer








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olivier is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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Disagree about 31, does not need concatenation : 29+1+0! = 31







share|improve this answer








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olivier is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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answered 48 mins ago









olivier

1




1




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olivier is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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olivier is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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  • This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
    – A. P.
    30 mins ago


















  • This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
    – A. P.
    30 mins ago
















This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
– A. P.
30 mins ago




This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
– A. P.
30 mins ago


















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