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

Terms

a(0) =1a(1) =1a(2) =3a(3) =8a(4) =20a(5) =47a(6) =118a(7) =280a(8) =681a(9) =1640a(10) =3963a(11) =9523a(12) =23004a(13) =55377a(14) =133477a(15) =321597a(16) =775054a(17) =1867304a(18) =4499934a(19) =10842847a(20) =26127768a(21) =62958232a(22) =151708512a(23) =365562567a(24) =880881465a(25) =2122617010a(26) =5114772619a(27) =12324827128a(28) =29698572295a(29) =71563264162