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PROJECT EULER · #0792

Too Many Twos

Statement only · UnsolvedOriginal problem ↗

We define ν2(n) to be the largest integer r such that 2r divides n. For example, ν2(24)=3.

Define S(n)=k=1n(2)k(2kk) and u(n)=ν2(3S(n)+4).

For example, when n=4 then S(4)=980 and 3S(4)+4=2944=2723, hence u(4)=7.
You are also given u(20)=24.

Also define U(N)=n=1Nu(n3). You are given U(5)=241.

Find U(104).

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