A373541 Expansion of e.g.f. exp(x/(1 + x^4)).

1, 1, 1, 1, 1, -119, -719, -2519, -6719, 347761, 5412961, 39861361, 199488961, -5448797639, -171814122479, -2172192782759, -17416977701759, 251989368889441, 15508068901698241, 302085533813309281, 3540741711640110721, -21311122660066333079

Offset: 0

Author

Seiichi Manyama, Jun 09 2024

Keywords

• sign

Crossrefs

Cf. A293507.

Programs

PARI

a(n) = n!*sum(k=0, n\4, (-1)^k*binomial(n-3*k-1, k)/(n-4*k)!);

Formula

a(n) = n! * Sum_{k=0..floor(n/4)} (-1)^k * binomial(n-3*k-1,k)/(n-4*k)!.

a(n) == 1 mod 120.