A366328 G.f. satisfies A(x) = (1 + x) * (1 + x/A(x)^4).

1, 2, -7, 60, -612, 6898, -82806, 1038076, -13431940, 178040315, -2405137161, 32992706368, -458336721104, 6435090557964, -91167680664004, 1301665779507128, -18710805300530504, 270559054510943509, -3932893180646204203, 57437414168562779574, -842365843304975785062

Offset: 0

Author

Seiichi Manyama, Oct 07 2023

Keywords

• sign

Crossrefs

Cf. A073157, A364336, A364337, A364338, A364339, A366325, A366326, A366327.

Cf. A118971, A364408.

Programs

PARI

a(n) = (-1)^(n-1)*sum(k=0, n, binomial(5*k-1, k)*binomial(n+3*k-2, n-k)/(5*k-1));

Formula

a(n) = (-1)^(n-1) * Sum_{k=0..n} binomial(5*k-1,k) * binomial(n+3*k-2,n-k)/(5*k-1).