A035381 Number of partitions of n into parts 6k+1 or 6k+3.

1, 1, 2, 2, 2, 3, 4, 4, 6, 7, 7, 9, 11, 12, 15, 18, 19, 23, 27, 29, 35, 41, 44, 51, 59, 64, 74, 86, 93, 106, 121, 131, 148, 169, 184, 206, 233, 253, 282, 318, 346, 384, 430, 467, 516, 576, 626, 689, 766, 831, 911, 1010, 1096, 1199, 1324, 1435, 1565, 1723, 1867

Offset

1,3

Links

Table of n, a(n) for n=1..59.

Formula

a(n) ~ exp(Pi*sqrt(2*n)/3) * Gamma(1/6) / (4 * 2^(5/12) * sqrt(3) * Pi^(5/6) * n^(7/12)). - Vaclav Kotesovec, Aug 27 2015

Mathematica

nmax = 100; Rest[CoefficientList[Series[Product[1/((1 - x^(6k+1))*(1 - x^(6k+3))), {k, 0, nmax}], {x, 0, nmax}], x]] (* Vaclav Kotesovec, Aug 27 2015 *)

Crossrefs

Sequence in context: A302404 A029050 A066920 * A096938 A130084 A017981

Adjacent sequences: A035378 A035379 A035380 * A035382 A035383 A035384

Keyword

nonn

Author

Olivier Gérard

Status

approved