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

Terms

a(0) =1a(1) =1a(2) =3a(3) =11a(4) =46a(5) =207a(6) =979a(7) =4796a(8) =24124a(9) =123862a(10) =646494a(11) =3420055a(12) =18296693a(13) =98817934a(14) =538065697a(15) =2950537937a(16) =16279888522a(17) =90317357884a(18) =503498509274