A384896 G.f. A(x) satisfies A(x) = 1 + x/A(-x*A(x))^3.

1, 1, 3, 0, -23, -51, 27, 920, 5469, 4836, -84822, -515991, -1733406, 2541688, 64653336, 324962160, 800371560, -3164656113, -49575569463, -260541998755, -734864189592, 1794936737274, 39518722602456, 260877913774320, 1122691536976305, 1485180173013631

Offset: 0

Author

Seiichi Manyama, Jun 12 2025

Keywords

• sign

Crossrefs

Column k=1 of A384901.

Cf. A001764, A213096, A384897, A384898.

Programs

PARI

a(n, k=-1) = if(n*k==0, 0^n, (-1)^n*k*sum(j=1, n, binomial(-n+2*j+k-1, j-1)*a(n-j, 3*j)/j));

Formula

See A384901.