A384941 G.f. A(x) satisfies A(x) = 1 + x/A(-x*A(x))^4.

1, 1, 4, -2, -64, -95, 780, 5230, 19228, -90488, -1454232, -4080620, 19557280, 270109125, 1702743364, -35378580, -74674412048, -515950535521, -1719717134140, 9100931191804, 173629815007712, 988336433707663, 2065106985108344, -25897495149473592

Offset: 0

Author

Seiichi Manyama, Jun 13 2025

Keywords

• sign

Crossrefs

Column k=1 of A384944.

Cf. A002293, A213101, A213102, A213103.

Cf. A000012, A384894, A384896, A384942, A384943.

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, 4*j)/j));

Formula

See A384944.