A261632 Expansion of Product_{k>=0} 1/(1-x^(4*k+1))^3.

1, 3, 6, 10, 15, 24, 37, 54, 75, 103, 144, 198, 265, 348, 456, 599, 777, 993, 1262, 1602, 2028, 2543, 3165, 3930, 4868, 6003, 7359, 8991, 10965, 13329, 16138, 19473, 23448, 28171, 33738, 40293, 48025, 57132, 67803, 80267, 94845, 111888, 131736, 154779, 181530

Offset

0,2

Links

Table of n, a(n) for n=0..44.

Formula

a(n) ~ exp(Pi*sqrt(n/2)) * 2^(3/8) * Gamma(1/4)^3 / (16 * Pi^(9/4) * n^(3/8)).

Mathematica

nmax=50; CoefficientList[Series[Product[1/(1-x^(4*k+1))^3, {k, 0, nmax}], {x, 0, nmax}], x]

Crossrefs

Cf. A035382, A261616, A261631, A035451, A261629.

Sequence in context: A117457 A024674 A026104 * A058576 A360893 A365696

Adjacent sequences: A261629 A261630 A261631 * A261633 A261634 A261635

Keyword

nonn

Author

Vaclav Kotesovec, Aug 27 2015

Status

approved