[Problem Statement](https://open.kattis.com/problems/sequences)↵
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[Code](https://hastebin.com/umiguvegat.cpp)↵
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I tried using the logic in [this blog post](http://codeforces.com/blog/entry/48143), but I keep getting WA. My code uses the identity 0*nC0+1*nC1+2*nC2+...+n*nCn = n*2^(n-1).↵
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Can someone please find the flaw in my counting method (or even better, provide a test case that breaks my code)?↵
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Thanks in advance!
↵
[Code](https://hastebin.com/umiguvegat.cpp)↵
↵
I tried using the logic in [this blog post](http://codeforces.com/blog/entry/48143), but I keep getting WA. My code uses the identity 0*nC0+1*nC1+2*nC2+...+n*nCn = n*2^(n-1).↵
↵
Can someone please find the flaw in my counting method (or even better, provide a test case that breaks my code)?↵
↵
Thanks in advance!
