A366056 Expansion of (1/x) * Series_Reversion( x*(1-x)^4/(1-x+x^4) ).

1, 3, 15, 91, 613, 4408, 33143, 257400, 2048825, 16625940, 137033316, 1144010387, 9653706723, 82208879366, 705587243802, 6097408839400, 53007770199641, 463269048213536, 4067950092964440, 35871913838983980, 317533385082542404, 2820492099258807887

Offset

0,2

Links

Table of n, a(n) for n=0..21.

Formula

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

Prog

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

Crossrefs

Cf. A215341, A366054, A366055.

Sequence in context: A366090 A171790 A006632 * A369161 A159928 A020018

Adjacent sequences: A366053 A366054 A366055 * A366057 A366058 A366059

Keyword

nonn

Author

Seiichi Manyama, Sep 27 2023

Status

approved