A365728 G.f. satisfies A(x) = 1 + x^4*A(x)^2*(1 + x*A(x)).

1, 0, 0, 0, 1, 1, 0, 0, 2, 5, 3, 0, 5, 21, 28, 12, 14, 84, 180, 165, 97, 330, 990, 1430, 1133, 1560, 5005, 10010, 11349, 11193, 25452, 61880, 94250, 100844, 150144, 360468, 683162, 889542, 1100784, 2144397, 4536839, 7158326, 9102786, 14132580, 29078645

Offset

0,9

Links

Table of n, a(n) for n=0..44.

Formula

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

Prog

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

Crossrefs

Cf. A365727, A365729, A365730, A365731.

Cf. A365696.

Sequence in context: A011035 A102892 A132898 * A265318 A279536 A269954

Adjacent sequences: A365725 A365726 A365727 * A365729 A365730 A365731

Keyword

nonn

Author

Seiichi Manyama, Sep 17 2023

Status

approved