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PROJECT EULER · #0635

Subset Sums

Statement only · UnsolvedOriginal problem ↗

Let Aq(n) be the number of subsets, B, of the set {1,2,...,qn} that satisfy two conditions:
1) B has exactly n elements;
2) the sum of the elements of B is divisible by n.

E.g. A2(5)=52 and A3(5)=603.

Let Sq(L) be Aq(p) where the sum is taken over all primes pL.
E.g. S2(10)=554, S2(100) mod 1000000009=100433628 and
S3(100) mod 1000000009=855618282.

Find S2(108)+S3(108). Give your answer modulo 1000000009.

Write-up coming later

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