A366088 Expansion of (1/x) * Series_Reversion( x*(1-x)^2/(1-x-x^4) ).

1, 1, 2, 5, 13, 35, 96, 264, 719, 1913, 4875, 11478, 22860, 26044, -77216, -793820, -4394125, -20304455, -85805571, -343282020, -1321898694, -4943906064, -18052305410, -64551823869, -226418611750, -779487689870, -2633172840764, -8717790419014

Offset

0,3

Links

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

Formula

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

Prog

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

Crossrefs

Cf. A366086, A366087, A366089, A366090.

Cf. A366054.

Sequence in context: A227045 A007075 A000107 * A370841 A063028 A085810

Adjacent sequences: A366085 A366086 A366087 * A366089 A366090 A366091

Keyword

sign

Author

Seiichi Manyama, Sep 28 2023

Status

approved