G.f. satisfies: A(x) = Product_{n>=1} (1 + x^(n+1)*A(x)) / (1 - x^n).

Terms

a(0) =1a(1) =1a(2) =3a(3) =6a(4) =14a(5) =31a(6) =72a(7) =166a(8) =390a(9) =922a(10) =2197a(11) =5273a(12) =12728a(13) =30892a(14) =75327a(15) =184476a(16) =453505a(17) =1118798a(18) =2768843a(19) =6872437a(20) =17103411a(21) =42670102a(22) =106697009a(23) =267359854a(24) =671260241a(25) =1688411587a(26) =4254084396a(27) =10735614274a(28) =27132998096a(29) =68671994940