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Number of partitions of n into parts 7k+2 or 7k+4.
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%I #8 Aug 26 2015 06:45:22

%S 0,1,0,2,0,2,0,3,1,3,2,4,3,4,4,6,5,8,6,11,7,14,9,17,12,20,17,23,22,27,

%T 28,33,34,41,40,52,47,63,56,76,69,88,85,103,105,119,126,142,149,169,

%U 173,203,201,241,236,282,279,326,332,375,392,433,460,504,532,589,612

%N Number of partitions of n into parts 7k+2 or 7k+4.

%F a(n) ~ exp(2*Pi*sqrt(n/21)) * Gamma(2/7) * Gamma(4/7) / (4 * 3^(5/28) * 7^(9/28) * Pi^(8/7) * n^(19/28)). - _Vaclav Kotesovec_, Aug 26 2015

%t nmax = 100; Rest[CoefficientList[Series[Product[1/((1 - x^(7k+2))*(1 - x^(7k+4))), {k, 0, nmax}], {x, 0, nmax}], x]] (* _Vaclav Kotesovec_, Aug 26 2015 *)

%K nonn

%O 1,4

%A _Olivier GĂ©rard_