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Expansion of Product_{k>=1} ((1 + x^(2*k-1))/(1 - x^(2*k-1)))^(k*(k-1)/2).
1

%I #5 Nov 08 2017 12:38:41

%S 1,0,0,2,0,6,2,12,12,22,42,42,114,102,264,280,564,744,1186,1866,2538,

%T 4380,5598,9732,12602,20898,28374,44048,63000,92190,137012,192864,

%U 291588,403668,609072,843228,1253978,1752150,2555058,3611380,5168778,7371324,10400908

%N Expansion of Product_{k>=1} ((1 + x^(2*k-1))/(1 - x^(2*k-1)))^(k*(k-1)/2).

%C Convolution of A294777 and A294778.

%F a(n) ~ exp(Pi * 2^(1/4) * n^(3/4)/3 - Pi*n^(1/4) / 2^(17/4) + 3*Zeta(3) / (32*Pi^2)) / (2^(37/16) * n^(5/8)).

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

%Y Cf. A206622, A292037, A294755, A294777, A294778, A294780.

%K nonn

%O 0,4

%A _Vaclav Kotesovec_, Nov 08 2017