A364761 G.f. satisfies A(x) = 1 / (1 + x*(1 + x*A(x))^3).

1, -1, -2, 5, 12, -41, -89, 391, 733, -4051, -6320, 44120, 54990, -496406, -465932, 5710408, 3637847, -66714699, -22683218, 787957397, 35371351, -9376925921, 2356626520, 112147043475, -61910867756, -1345231820826, 1158452138826, 16156200619772

Offset

0,3

Links

Table of n, a(n) for n=0..27.

Formula

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

Prog

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

Crossrefs

Cf. A007440, A364760, A364762, A364763.

Cf. A364742.

Sequence in context: A203151 A140440 A005664 * A009739 A062272 A215789

Adjacent sequences: A364758 A364759 A364760 * A364762 A364763 A364764

Keyword

sign

Author

Seiichi Manyama, Aug 05 2023

Status

approved