A366592 G.f. A(x) satisfies A(x) = 1 + x^4*(1+x)^2*A(x)^3.

1, 0, 0, 0, 1, 2, 1, 0, 3, 12, 18, 12, 15, 72, 180, 240, 235, 512, 1552, 3080, 4123, 5810, 13825, 33200, 58813, 85932, 151578, 346920, 726897, 1242234, 2025177, 3952704, 8509875, 16525872, 28565064, 50849280, 102266019, 208932438, 391951131, 699037248, 1313756457

Offset

0,6

Links

Table of n, a(n) for n=0..40.

Formula

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

Prog

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

Crossrefs

Cf. A366221, A366590, A366591.

Cf. A366556.

Sequence in context: A356263 A320825 A161552 * A095859 A349627 A300482

Adjacent sequences: A366589 A366590 A366591 * A366593 A366594 A366595

Keyword

nonn

Author

Seiichi Manyama, Oct 14 2023

Status

approved