Expansion of Product_{k>=1} 1/(1 - x^k)^(k*(3*k-1)*(3*k-2)/2).

Terms

a(0) =1a(1) =1a(2) =21a(3) =105a(4) =535a(5) =2670a(6) =12996a(7) =59546a(8) =266875a(9) =1161894a(10) =4939778a(11) =20528320a(12) =83636061a(13) =334496221a(14) =1315381029a(15) =5091782355a(16) =19424086781a(17) =73092029218a(18) =271537720562a(19) =996656173345