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

Terms

a(0) =1a(1) =2a(2) =2a(3) =6a(4) =40a(5) =208a(6) =798a(7) =3122a(8) =15038a(9) =77830a(10) =381798a(11) =1819998a(12) =8925172a(13) =45280900a(14) =231030138a(15) =1171823534a(16) =5962836408a(17) =30668699312a(18) =158951012362a(19) =825830001086