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A022610
Expansion of Product_{m>=1} (1+q^m)^(-15).
3
1, -15, 105, -470, 1590, -4593, 12160, -30075, 69780, -153750, 325728, -667020, 1323915, -2557140, 4824630, -8912759, 16148505, -28746945, 50364835, -86956260, 148098384, -249060745, 413975085, -680602545
OFFSET
0,2
COMMENTS
a(0) = 1, a(n) = -(15/n)*Sum_{k=1..n} A000593(k)*a(n-k) for n > 0. - Seiichi Manyama, Apr 05 2017
LINKS
FORMULA
a(n) ~ (-1)^n * 5^(1/4) * exp(Pi*sqrt(5*n/2)) / (2^(7/4) * n^(3/4)). - Vaclav Kotesovec, Aug 27 2015
MATHEMATICA
nmax = 50; CoefficientList[Series[Product[1/(1 + x^k)^15, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Aug 27 2015 *)
CROSSREFS
Sequence in context: A010931 A282350 A076767 * A006857 A000478 A055848
KEYWORD
sign
STATUS
approved