A366366 G.f. satisfies A(x) = (1 + x/A(x)^4)/(1 - x).

1, 2, -6, 58, -574, 6402, -75878, 939290, -12000318, 157050178, -2094657926, 28368411194, -389079656446, 5393118559938, -75431624084838, 1063251390845338, -15088643098754942, 215396586102923138, -3091050571516120582, 44566089825496186170

Offset: 0

Author

Seiichi Manyama, Oct 08 2023

Keywords

• sign

Crossrefs

Cf. A346626, A349310, A349311, A349312, A349313, A349314, A366363, A366364, A366365.

Cf. A366359.

Programs

PARI

a(n) = (-1)^(n-1)*sum(k=0, n, binomial(5*k-1, k)*binomial(4*k-1, n-k)/(5*k-1));

Formula

a(n) = (-1)^(n-1) * Sum_{k=0..n} binomial(5*k-1,k) * binomial(4*k-1,n-k)/(5*k-1).