A373667 Expansion of e.g.f. exp(x / (1 - x^2)^(5/2)).

1, 1, 1, 16, 61, 676, 5701, 60376, 798841, 9635536, 160878601, 2367914176, 44902245301, 807083463616, 16799688310861, 358223448539776, 8158048770370801, 199405713714155776, 4987832102850957841, 135848995301247809536, 3737769145322321702701

Offset

0,4

Links

Table of n, a(n) for n=0..20.

Formula

a(n) = n! * Sum_{k=0..floor(n/2)} binomial(5*n/2-4*k-1,k)/(n-2*k)!.

a(n) == 1 (mod 15).

Prog

(PARI) a(n) = n!*sum(k=0, n\2, binomial(5*n/2-4*k-1, k)/(n-2*k)!);

Crossrefs

Cf. A012150, A088009, A373619, A373620, A373668.

Sequence in context: A317431 A241523 A264632 * A007831 A214524 A118254

Adjacent sequences: A373664 A373665 A373666 * A373668 A373669 A373670

Keyword

nonn

Author

Seiichi Manyama, Jun 13 2024

Status

approved