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

Terms

a(0) =1a(1) =2a(2) =4a(3) =11a(4) =35a(5) =121a(6) =444a(7) =1689a(8) =6592a(9) =26258a(10) =106313a(11) =436203a(12) =1809727a(13) =7579202a(14) =31999297a(15) =136050472a(16) =582002281a(17) =2503242025a(18) =10818689627a(19) =46959246659a(20) =204623676444a(21) =894785832949