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A167531
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a(n) = Sum_{d divides n} d*(n/d)^(d-1).
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12
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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
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OFFSET
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1,2
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LINKS
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FORMULA
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G.f.: Sum{k>0} x^k/(1-k*x^k)^2.
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PROG
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(PARI) a(n)=sumdiv(n, d, d*(n/d)^(d-1))
(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
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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