A384984 E.g.f. A(x) satisfies A(x) = exp(x*A(x)/A(-x*A(x)^6)^3).

1, 1, 9, 133, 3185, 88521, 2709625, 59590189, -2800437663, -743713824239, -109790487971479, -14561409462651435, -1895796404420991023, -246003292448561592359, -31576403033658804388647, -3869259020245783760710019, -407064058939470167525999935, -20441215103072839391579678175

Offset: 0

Author

Seiichi Manyama, Jun 14 2025

Keywords

• sign

Crossrefs

Column k=1 of A384987.

Programs

PARI

a(n, k=-1) = if(n*k==0, 0^n, (-1)^n*k*sum(j=1, n, (-6*n+5*j+k)^(j-1)*binomial(n, j)*a(n-j, 3*j)));

Formula

See A384987.