G.f. satisfies A(x) = 1 + x*A(x)^4 + x^2*A(x).

Terms

a(0) =1a(1) =1a(2) =5a(3) =27a(4) =177a(5) =1270a(6) =9645a(7) =76206a(8) =619913a(9) =5156959a(10) =43667985a(11) =375140383a(12) =3261467573a(13) =28641957520a(14) =253702185717