Expansion of Product_{k>=1} (1 + x^k)^(k*(k+1)*(4*k-1)/6).

Terms

a(0) =1a(1) =1a(2) =7a(3) =29a(4) =93a(5) =320a(6) =1026a(7) =3256a(8) =9995a(9) =30102a(10) =88722a(11) =257042a(12) =732876a(13) =2058370a(14) =5703858a(15) =15606076a(16) =42203027a(17) =112882223a(18) =298849221a(19) =783574536a(20) =2035876825a(21) =5244191462a(22) =13398463986a(23) =33967008194a(24) =85476285603a(25) =213583335753a(26) =530099612487