A365226 G.f. satisfies A(x) = 1 + x*A(x)^5 / (1 + x*A(x)^6).

1, 1, 4, 20, 107, 577, 3010, 14429, 56640, 98020, -1297568, -21901213, -232421636, -2081040375, -16862259358, -126674303915, -887771735205, -5768588276072, -33971373570320, -170393703586467, -576946353425125, 1101490168511323, 47657979846612682

Offset

0,3

Links

Table of n, a(n) for n=0..22.

Formula

a(n) = Sum_{k=0..n} (-1)^(n-k) * binomial(6*n-k+1,k) * binomial(n-1,n-k)/(6*n-k+1).

Prog

(PARI) a(n) = sum(k=0, n, (-1)^(n-k)*binomial(6*n-k+1, k)*binomial(n-1, n-k)/(6*n-k+1));

Crossrefs

Cf. A002293, A271469, A349361, A364759, A364866, A365225.

Cf. A365218.

Sequence in context: A190724 A243585 A359712 * A263965 A265084 A321111

Adjacent sequences: A365223 A365224 A365225 * A365227 A365228 A365229

Keyword

sign

Author

Seiichi Manyama, Aug 27 2023

Status

approved