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 A294645 a(n) = Sum_{d|n} d^(n+1). 8
 1, 9, 82, 1057, 15626, 282252, 5764802, 134480385, 3486843451, 100048830174, 3138428376722, 107006334784468, 3937376385699290, 155572843119354936, 6568408508343827972, 295150156996346511361, 14063084452067724991010, 708236696816416252145973 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Seiichi Manyama, Table of n, a(n) for n = 1..385 Eric Weisstein's World of Mathematics, Divisor Function FORMULA G.f.: Sum_{k>0} k^(k+1)*x^k/(1-(k*x)^k). L.g.f.: -log(Product_{k>=1} (1 - (k*x)^k)) = Sum_{k>=1} a(k)*x^k/k. - Seiichi Manyama, Jun 02 2019 PROG (PARI) {a(n) = sigma(n, n+1)} (PARI) N=66; x='x+O('x^N); Vec(sum(k=1, N, k^(k+1)*x^k/(1-(k*x)^k))) (PARI) N=20; x='x+O('x^N); Vec(x*deriv(-log(prod(k=1, N, 1-(k*x)^k)))) \\ Seiichi Manyama, Jun 02 2019 CROSSREFS Column k=1 of A308504. Cf. A023882, A023887, A082245, A292312. Sequence in context: A045741 A283498 A294956 * A308668 A308481 A041146 Adjacent sequences:  A294642 A294643 A294644 * A294646 A294647 A294648 KEYWORD nonn AUTHOR Seiichi Manyama, Nov 05 2017 STATUS approved

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Last modified December 9 03:27 EST 2019. Contains 329872 sequences. (Running on oeis4.)