A327690 Expansion of Product_{k>=1} B(x^k), where B(x) is the g.f. of A003114.

1, 1, 2, 3, 6, 8, 14, 19, 31, 43, 64, 88, 131, 176, 250, 337, 471, 626, 859, 1133, 1532, 2008, 2674, 3479, 4595, 5933, 7745, 9952, 12888, 16451, 21142, 26842, 34260, 43283, 54878, 68993, 87017, 108884, 136564, 170191, 212441, 263646, 327616, 405034, 501203, 617423, 760964

Offset: 0

Author

Seiichi Manyama, Sep 22 2019

Keywords

• nonn

Links

• Vaclav Kotesovec, Table of n, a(n) for n = 0..10000 (terms 0..1000 from Seiichi Manyama)

Crossrefs

Cf. A003114, A327688, A327691.

Programs

Mathematica

nmax = 50; CoefficientList[Series[Product[1/(QPochhammer[x^(5*j - 4)] * QPochhammer[x^(5*j - 1)]), {j, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Sep 23 2019 *)

Formula

G.f.: Product_{i>=1} Product_{j>=1} 1 / ((1-x^(i*(5*j-1))) * (1-x^(i*(5*j-4)))).