Problem 42834. Integer complexity (Large numbers)

Created by Peng Liu

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Last Solution submitted on Dec 30, 2022

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Solution 906063

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Rafael S.T. Vieira on 19 Sep 2020

I was obtaining 34 for 7e4 too, but it's not a problem of the test suite. It just means that your code is not testing all possible combinations (and there are probably other numbers that will fail too). There is no known algorithm to generate the list of integer complexity (https://oeis.org/A005245), which means brute force is the only way to be sure. And brute force finds 32 for 7e4.

Rafael S.T. Vieira on 19 Sep 2020

It someone doesn't believe 7e4 = (1+1)*(1+1)*(1+1)*(1+1)*(1+ (1+1)*(1+1+1)*(1+1+1)*(1+1+1)*(1+1+1)*(1+1+1)*(1+1+1)*(1+1+1)) (32 ones). Or 2^4*(1 + 2*3^7).

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Problem 42834. Integer complexity (Large numbers)

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Problem 42834. Integer complexity (Large numbers)

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