A366084 Expansion of (1/x) * Series_Reversion( x*(1-x)^3/(1-x-x^3) ).

1, 2, 7, 29, 132, 637, 3199, 16536, 87366, 469556, 2558610, 14100033, 78437805, 439838596, 2483300228, 14103794518, 80517436710, 461768157262, 2658979794811, 15366500638407, 89093023210674, 518064484263918, 3020484579372765, 17653011431832906

Offset

0,2

Links

Seiichi Manyama, Table of n, a(n) for n = 0..1000

Formula

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

Prog

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

Crossrefs

Cf. A049133, A243157, A366085.

Cf. A366052.

Sequence in context: A007852 A300048 A232971 * A368935 A110576 A074600

Adjacent sequences: A366081 A366082 A366083 * A366085 A366086 A366087

Keyword

sign

Author

Seiichi Manyama, Sep 28 2023

Status

approved