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A261651 Expansion of Product_{k>=0} ((1+x^(3*k+1))/(1-x^(3*k+1)))^3. 3

%I

%S 1,6,18,38,72,138,254,432,708,1154,1836,2826,4288,6456,9552,13902,

%T 20070,28722,40614,56916,79242,109448,149988,204318,276672,372288,

%U 498264,663602,879252,1159470,1522564,1990788,2592162,3362638,4346244,5597100,7183792,9191004

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

%F a(n) ~ exp(Pi*sqrt(n)) * Gamma(1/3)^3 / (4 * Pi^2 * sqrt(3*n)).

%t nmax=60; CoefficientList[Series[Product[((1+x^(3*k+1))/(1-x^(3*k+1)))^3,{k,0,nmax}],{x,0,nmax}],x]

%Y Cf. A015128, A156616, A080054, A007096, A261610, A261649.

%K nonn

%O 0,2

%A _Vaclav Kotesovec_, Aug 28 2015

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Last modified November 11 18:50 EST 2019. Contains 329031 sequences. (Running on oeis4.)