%I #6 Dec 15 2015 18:59:17

%S 1,0,2,0,4,5,8,10,24,20,73,51,146,142,306,409,731,835,1662,1828,3969,

%T 4251,8256,9525,17814,22565,38629,47424,82916,101387,185271,218421,

%U 386140,468783,806005,1040428,1696283,2160026,3567221,4498026,7683250,9446666

%N Expansion of Product_{k>=1} 1/(1 - (3*k-1)*x^(3*k-1)).

%H Vaclav Kotesovec, <a href="/A265820/b265820.txt">Table of n, a(n) for n = 0..5000</a>

%F a(n) ~ c * 2^(n/2), where

%F c = 14.317325023208603416271945494838289608390197678435231... if n is even,

%F c = 13.388403642510880418401945468592189683402616378443965... if n is odd.

%t nmax = 40; CoefficientList[Series[Product[1/(1 - (3*k-1)*x^(3*k-1)), {k, 1, nmax}], {x, 0, nmax}], x]

%Y Cf. A067553, A265821.

%K nonn

%O 0,3

%A _Vaclav Kotesovec_, Dec 15 2015