G.f. satisfies: A(x) = 1 + x*A(x)^5/A(-x).

Terms

a(0) =1a(1) =1a(2) =6a(3) =40a(4) =374a(5) =3215a(6) =34298a(7) =326360a(8) =3710278a(9) =37289620a(10) =440121880a(11) =4577214736a(12) =55375589594a(13) =589530372890