G.f. satisfies A(x) = 1 + x^3 + x*A(x)^4.

Terms

a(0) =1a(1) =1a(2) =4a(3) =23a(4) =144a(5) =997a(6) =7304a(7) =55646a(8) =436320a(9) =3497846a(10) =28538852a(11) =236203518a(12) =1978290648a(13) =16735471979a(14) =142789868112