A293387 Expansion of (eta(q^2)^2/(eta(q)eta(q^3)))^2 in powers of q.

1, 2, 1, 4, 6, 2, 12, 16, 5, 28, 36, 12, 60, 76, 24, 120, 150, 46, 228, 280, 86, 416, 504, 152, 732, 878, 262, 1252, 1488, 442, 2088, 2464, 725, 3408, 3996, 1168, 5460, 6364, 1852, 8600, 9972, 2886, 13344, 15400, 4436, 20424, 23472, 6736, 30876, 35346, 10103

Offset: 0

Author

Seiichi Manyama, Oct 07 2017

Keywords

• nonn

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..10000

Crossrefs

Cf. A262930, A292577.

Programs

Mathematica

nmax = 100; CoefficientList[Series[Product[((1 - x^(2*k))^2/((1 - x^k)*(1 - x^(3*k))))^2, {k, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Oct 08 2017 *)

Formula

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