A325951 G.f.: 1/(1-x)^3 * Product_{k>=1} (1 + x^k).

1, 4, 10, 21, 39, 67, 109, 170, 256, 375, 537, 754, 1041, 1416, 1901, 2523, 3314, 4312, 5563, 7121, 9050, 11426, 14338, 17890, 22204, 27422, 33709, 41257, 50288, 61058, 73863, 89043, 106988, 128146, 153029, 182222, 216393, 256302, 302813, 356908, 419700

Offset

0,2

Links

Table of n, a(n) for n=0..40.

Formula

a(n) ~ 2 * 3^(5/4) * n^(3/4) * exp(Pi*sqrt(n/3)) / Pi^3.

Mathematica

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

Crossrefs

Cf. A000009, A014160, A036469, A095944, A120477, A292508.

Sequence in context: A049480 A216172 A055908 * A023538 A085360 A265050

Adjacent sequences: A325948 A325949 A325950 * A325952 A325953 A325954

Keyword

nonn

Author

Vaclav Kotesovec, May 28 2019

Status

approved