Expansion of Product_{k>=1} (1 + x^k)^binomial(k+2,2).

Terms

a(0) =1a(1) =3a(2) =9a(3) =29a(4) =78a(5) =207a(6) =526a(7) =1284a(8) =3054a(9) =7084a(10) =16071a(11) =35748a(12) =78167a(13) =168195a(14) =356754a(15) =746772a(16) =1544145a(17) =3157056a(18) =6387114a(19) =12795366a(20) =25397760a(21) =49977262a(22) =97542936a(23) =188912466a(24) =363196750a(25) =693424803a(26) =1315161528a(27) =2478648920a(28) =4643337213a(29) =8648452782