G.f. satisfies: A(x) = Sum_{n>=0} x^n * (1 + x*A(x)^(n-1))^n.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =7a(5) =20a(6) =63a(7) =215a(8) =783a(9) =2998a(10) =11977a(11) =49656a(12) =212738a(13) =938836a(14) =4257792a(15) =19808597a(16) =94405713a(17) =460412410a(18) =2295740045a(19) =11695447378a(20) =60837384509a(21) =322968172763