G.f. A(x) satisfies: A( x*A(x) - A(x)^3 ) = x^2.

Terms

a(0) =1a(1) =1a(2) =2a(3) =9a(4) =40a(5) =192a(6) =959a(7) =4988a(8) =26587a(9) =144672a(10) =800229a(11) =4486914a(12) =25444355a(13) =145681030a(14) =840988369a(15) =4889658927a(16) =28607653570a(17) =168299372745a(18) =994978254267