G.f. A(x) satisfies: A(A(A(x))) = x + 9*x^2.

A141118

G.f. A(x) satisfies: A(A(A(x))) = x + 9*x^2.

Terms

    a(0) =1a(1) =3a(2) =-18a(3) =189a(4) =-2430a(5) =34020a(6) =-486972a(7) =6786261a(8) =-86946372a(9) =919825956a(10) =-5269375296a(11) =-80180038944

External references