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%I #12 Sep 07 2023 15:52:13
%S 1,1,17,98,610,2531,18580,72453,449494,2114440,10753594,48572844,
%T 272867295,1137441506,5834448870,27276382027,129389072144,
%U 576677550870,2884567552542,12401875640710,59474089385344,270438887909580,1230979340265033,5477371267093144
%N Expansion of Product_{k>=1} 1/(1 - k^4*x^k).
%H Vaclav Kotesovec, <a href="/A265838/b265838.txt">Table of n, a(n) for n = 0..1550</a>
%F a(n) ~ c * 3^(4*n/3), where
%F c = 27.2472595510480930563087281042486261391960582835336715327... if n mod 3 = 0
%F c = 26.8841208067599453033952496040472485838861626762931432887... if n mod 3 = 1
%F c = 26.9277867007233095885556073185206409643421012262073908850... if n mod 3 = 2.
%F G.f.: exp(Sum_{k>=1} Sum_{j>=1} j^(4*k)*x^(j*k)/k). - _Ilya Gutkovskiy_, Jun 14 2018
%t nmax = 40; CoefficientList[Series[Product[1/(1 - k^4*x^k), {k, 1, nmax}], {x, 0, nmax}], x]
%Y Cf. A006906, A077335, A265837, A265839, A265841.
%Y Column k=4 of A292193.
%K nonn
%O 0,3
%A _Vaclav Kotesovec_, Dec 16 2015
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