A385606 Diagonal of the rational function 1/(1 - (v^3 + w^3 + x^3 + y^3 + z^3 + v*w*x*y*z)).

1, 1, 1, 121, 721, 2521, 120121, 1262521, 7514641, 200655841, 2804296441, 23211542641, 443673670441, 7070369866561, 73192033638361, 1173608444069881, 19482750854113681, 235115468646608881, 3483568444035458401, 57574418930692099801, 769737183831483390601, 11118980118960559362001

Offset

0,4

Links

Table of n, a(n) for n=0..21.

Formula

a(n) = Sum_{k=0..floor(n/3)} (n+2*k)!/(k!^5 * (n-3*k)!).

Prog

(PARI) a(n) = sum(k=0, n\3, (n+2*k)!/(k!^5*(n-3*k)!));

Crossrefs

Cf. A082489, A361636, A361703, A385607.

Sequence in context: A293566 A293507 A356630 * A385607 A306452 A238250

Adjacent sequences: A385603 A385604 A385605 * A385607 A385608 A385609

Keyword

nonn

Author

Seiichi Manyama, Jul 04 2025

Status

approved