G.f. A(x) satisfies: A(A(A(A(x)))) = G(x) where G(x) = x + 3*x^2 + x*G(G(G(G(x)))) is the g.f. of A215116.
A215117
G.f. A(x) satisfies: A(A(A(A(x)))) = G(x) where G(x) = x + 3*x^2 + x*G(G(G(G(x)))) is the g.f. of A215116.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =49a(4) =721a(5) =17281a(6) =452065a(7) =13511953a(8) =443435185a(9) =15816390241a(10) =606861668161
External references
- oeis: A215117