G.f. satisfies A(x) = 1 + x*A(x)^3 + x^3*A(x)^6.

Terms

a(0) =1a(1) =1a(2) =3a(3) =13a(4) =64a(5) =339a(6) =1889a(7) =10917a(8) =64836a(9) =393292a(10) =2426335a(11) =15176847a(12) =96029114a(13) =613540477a(14) =3952727925a(15) =25649572693a(16) =167494312692