A379286 G.f. A(x) satisfies A(x) = 1/((1 - x*A(x)^2) * (1 - x*A(x)^5)).

1, 2, 17, 209, 3025, 47975, 806673, 14126236, 254880645, 4705443504, 88458542000, 1687588704861, 32589587581341, 635824437818621, 12513756861585915, 248148065577971460, 4953215882123744005, 99442753396113435246, 2006704742456528041800, 40679834776076235917841

Offset

0,2

Links

Table of n, a(n) for n=0..19.

Formula

a(n) = Sum_{k=0..n} binomial(2*n+4*k+1,k) * binomial(3*n+2*k,n-k)/(2*n+4*k+1).

Prog

(PARI) a(n) = sum(k=0, n, binomial(2*n+4*k+1, k)*binomial(3*n+2*k, n-k)/(2*n+4*k+1));

Crossrefs

Cf. A118969, A199475, A379209, A379284, A379285, A379287.

Sequence in context: A364335 A364446 A333990 * A349654 A364333 A370289

Adjacent sequences: A379283 A379284 A379285 * A379287 A379288 A379289

Keyword

nonn

Author

Seiichi Manyama, Dec 19 2024

Status

approved