A327691 Expansion of Product_{k>=1} B(x^k), where B(x) is the g.f. of A003106.

1, 0, 1, 1, 2, 1, 5, 3, 8, 7, 13, 11, 26, 20, 40, 39, 66, 61, 111, 102, 171, 174, 266, 269, 427, 423, 638, 675, 969, 1016, 1477, 1544, 2177, 2350, 3209, 3466, 4754, 5112, 6867, 7546, 9931, 10899, 14343, 15729, 20406, 22653, 28962, 32168, 41069, 45561, 57551, 64382, 80491, 90030, 112286

Offset

0,5

Links

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

Formula

G.f.: Product_{i>=1} Product_{j>=1} 1 / ((1-x^(i*(5*j-2))) * (1-x^(i*(5*j-3)))).

Mathematica

nmax = 50; CoefficientList[Series[Product[1/(QPochhammer[x^(5*j - 3)] * QPochhammer[x^(5*j - 2)]), {j, 1, nmax}], {x, 0, nmax}], x] (* Vaclav Kotesovec, Sep 23 2019 *)

Crossrefs

Cf. A003106, A327688, A327690.

Sequence in context: A026205 A082748 A342131 * A175330 A333259 A334172

Adjacent sequences: A327688 A327689 A327690 * A327692 A327693 A327694

Keyword

nonn

Author

Seiichi Manyama, Sep 22 2019

Status

approved