A167531 a(n) = Sum_{d divides n} d*(n/d)^(d-1).
1, 3, 4, 9, 6, 25, 8, 49, 37, 101, 12, 373, 14, 477, 496, 1313, 18, 3907, 20, 6941, 5272, 11309, 24, 49321, 3151, 53301, 59320, 144789, 30, 468181, 32, 657473, 649936, 1114181, 121416, 5124961, 38, 4980813, 6909280, 13756761, 42, 44768725, 44
Offset: 1
Keywords
Links
- Seiichi Manyama, Table of n, a(n) for n = 1..5000
Programs
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PARI
a(n)=sumdiv(n,d,d*(n/d)^(d-1))
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PARI
N=66; x='x+O('x^N); Vec(sum(k=1, N, x^k/(1-k*x^k)^2)) \\ Seiichi Manyama, Sep 03 2019
Formula
G.f.: Sum{k>0} x^k/(1-k*x^k)^2.