G.f. A(x) satisfies: A(x) = (1 + x) * A(x^2)^2*A(x^3)^3*A(x^4)^4* ... *A(x^k)^k* ...

Terms

a(0) =1a(1) =1a(2) =2a(3) =5a(4) =12a(5) =20a(6) =48a(7) =81a(8) =169a(9) =305a(10) =580a(11) =1009a(12) =1966a(13) =3338a(14) =6067a(15) =10503a(16) =18730a(17) =31633a(18) =55641a(19) =93151a(20) =160389a(21) =267585a(22) =452762a(23) =747016a(24) =1253644a(25) =2049943a(26) =3390786a(27) =5516227a(28) =9034745a(29) =14572790