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A038066
Product_{k>=1} 1/(1 - x^k)^a(k) = 1 + 5x.
6
5, -15, 40, -150, 624, -2620, 11160, -48750, 217000, -976872, 4438920, -20343700, 93900240, -435970980, 2034504992, -9536718750, 44878791360, -211927733500, 1003867701480, -4768371093720, 22706531339280
OFFSET
1,1
LINKS
N. J. A. Sloane, Euler transform
FORMULA
G.f.: Sum_{k>=1} mu(k)*log(1 + 5*x^k)/k. - Ilya Gutkovskiy, May 23 2017
a(n) ~ -(-1)^n * 5^n / n. - Vaclav Kotesovec, Jun 12 2018
PROG
(PARI) x='x+O('x^22); Vec(sum(k=1, 22, moebius(k)*log(1 + 5*x^k)/k)) \\ Indranil Ghosh, May 24 2017
KEYWORD
sign
AUTHOR
Christian G. Bower, Jan 04 1999
STATUS
approved