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Problem 719

Posted: Fri Sep 11, 2020 3:53 pm
by scienalc
My algorithm found 7 S-Numbers lesser or equal than 10000 with a sum of 31233. The given sum is 41333, however.

Just to make clear I understood the problem statement, please confirm or correct the following statements:
  • only addition is allowed, i.e. one can't subtract or similar
  • the order of the digits must me observed, i.e. it is not allowed to convert 6724 to 62 + 7 + 4, for example
I also manually looked through the first 100 numbers and didn't find any that could meet the criteria.

These are the S-Numbers my algorithm found: 81, 1296, 2025, 3025, 6724, 8281, 9801. Which am I missing? (I don't consider them spoilers, as they don't reveal anything about the algorithm, but if they are, feel free to remove them)

Re: Problem 719

Posted: Sat Sep 12, 2020 12:14 am
by Ted
You'll smack your forehead when you find the missing 10100. Just remember that zeros can be addends.

Re: Problem 719

Posted: Sat Sep 12, 2020 1:37 pm
by scienalc
Ted wrote: Sat Sep 12, 2020 12:14 am You'll smack your forehead when you find the missing 10100. Just remember that zeros can be addends.
I did, I literally did. The error wasn't even in the core part of the algorithm, but in the part of code that determines the number of digits - it was off by one in those cases.