G.f. B(x) satisfies: B(x) = x + 3*A(x)*C(x), where A(x) = x + 2*B(x)*C(x) and C(x) = x + 5*A(x)*B(x).
A229809
G.f. B(x) satisfies: B(x) = x + 3*A(x)*C(x), where A(x) = x + 2*B(x)*C(x) and C(x) = x + 5*A(x)*B(x).
Terms
- a(0) =1a(1) =3a(2) =21a(3) =153a(4) =1401a(5) =13083a(6) =130401a(7) =1334613a(8) =14048481a(9) =150675363a(10) =1642689501a(11) =18141639153a(12) =202569926121
External references
- oeis: A229809