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Expansion of (eta(q^6)/(eta(q)*eta(q^2)*eta(q^3)))^2 in powers of q.
2

%I #18 Dec 11 2023 15:11:00

%S 1,2,7,16,39,80,171,328,638,1168,2133,3744,6540,11092,18687,30816,

%T 50421,81136,129582,204160,319340,493952,758781,1154624,1745748,

%U 2617958,3902614,5776144,8501784,12434320,18092565,26175784,37689734,53989056,76993497,109284736

%N Expansion of (eta(q^6)/(eta(q)*eta(q^2)*eta(q^3)))^2 in powers of q.

%H Seiichi Manyama, <a href="/A293378/b293378.txt">Table of n, a(n) for n = 0..10000</a>

%F G.f.: Product_{k>0} ((1 - x^(6*k))/((1 - x^k)*(1 - x^(2*k))*(1 - x^(3*k))))^2.

%F a(n) ~ 5^(5/4) * exp(2*Pi*sqrt(5*n)/3) / (72 * sqrt(3) * n^(7/4)). - _Vaclav Kotesovec_, Oct 11 2017

%t nmax = 50; CoefficientList[Series[Product[((1 + x^(3*k))/((1 - x^k)*(1 - x^(2*k))))^2, {k, 1, nmax}], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Oct 11 2017 *)

%Y Cf. A077285, A293377.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Oct 07 2017