A015057 q-Catalan numbers (binomial version) for q=-3.

1, 1, 10, 793, 583102, 3815415802, 225503698948660, 119805449249886397129, 573084012222813752884459126, 24668552204097304242240261360949726, 9557210465694593089306513607806406698372300

Offset

0,3

Links

Table of n, a(n) for n=0..10.

Formula

{1 / (n+1)_q} {2 n choose n}_q.

Mathematica

Table[4 QBinomial[2n, n, -3]/(1 - (-3)^(n+1)), {n, 0, 20}] (* Vladimir Reshetnikov, Sep 16 2016 *)

Crossrefs

Sequence in context: A222689 A242373 A221045 * A302133 A322918 A233170

Adjacent sequences: A015054 A015055 A015056 * A015058 A015059 A015060

Keyword

nonn,easy

Author

Olivier Gérard

Status

approved