A384720 E.g.f. A(x) satisfies A(x) = exp( x * A(x*A(x))^3 ).

1, 1, 7, 118, 3385, 141556, 7918489, 561302470, 48589734337, 5001284972872, 599865865782481, 82534986682048066, 12863925185682542833, 2248009460254706256460, 436716594440553989797369, 93635975845903995553159126, 22021353830468757164023479169, 5650417076648052544704264390160

Offset: 0

Author

Seiichi Manyama, Jun 08 2025

Keywords

• nonn

Crossrefs

Column k=1 of A384722.

Cf. A162659, A384719.

Programs

PARI

a(n, k=1) = if(k==0, 0^n, k*sum(j=0, n, (n-j+k)^(j-1)*binomial(n, j)*a(n-j, 3*j)));

Formula

See A384722.