A132305 Sum of fifth powers of trinomial coefficients: a(n) = Sum_{k=0..2n} trinomial(n,k)^5 where trinomial(n,k) = [x^k] (1 + x + x^2)^n.

1, 3, 309, 32847, 4775301, 764206503, 131689759209, 23857704965727, 4487745064421061, 869024373004460823, 172218243516497425809, 34778752398142969125627, 7134304921516864247956281

Offset

0,2

Links

Table of n, a(n) for n=0..12.

Prog

(PARI) a(n)=sum(k=0, 2*n, polcoeff((1+x+x^2)^n, k)^5)

Crossrefs

Cf. A132303, A132304.

Sequence in context: A218361 A085319 A123032 * A074327 A179109 A316329

Adjacent sequences: A132302 A132303 A132304 * A132306 A132307 A132308

Keyword

nonn

Author

Paul D. Hanna, Aug 18 2007

Status

approved