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

Terms

a(0) =1a(1) =1a(2) =3a(3) =12a(4) =57a(5) =300a(6) =1697a(7) =10126a(8) =62991a(9) =405247a(10) =2680901a(11) =18160444a(12) =125562250a(13) =883868590a(14) =6321838520a(15) =45869309028a(16) =337167193262