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 A022608 Expansion of Product_{m>=1} (1+q^m)^(-13). 2

%I

%S 1,-13,78,-299,884,-2314,5681,-13052,28158,-58136,116129,-224692,

%T 422214,-774372,1390948,-2450565,4240561,-7221383,12121980,-20076953,

%U 32836752,-53089309,84922877,-134488770,210979548

%N Expansion of Product_{m>=1} (1+q^m)^(-13).

%H Seiichi Manyama, <a href="/A022608/b022608.txt">Table of n, a(n) for n = 0..10000</a>

%F a(n) ~ (-1)^n * 13^(1/4) * exp(Pi*sqrt(13*n/6)) / (2^(7/4) * 3^(1/4) * n^(3/4)). - _Vaclav Kotesovec_, Aug 27 2015

%F a(0) = 1, a(n) = -(13/n)*Sum_{k=1..n} A000593(k)*a(n-k) for n > 0. - _Seiichi Manyama_, Apr 05 2017

%t nmax = 50; CoefficientList[Series[Product[1/(1 + x^k)^13, {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Aug 27 2015 *)

%K sign

%O 0,2

%A _N. J. A. Sloane_

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Last modified October 18 08:03 EDT 2019. Contains 328146 sequences. (Running on oeis4.)