English

Sums of powers of Catalan triangle numbers

Number Theory 2016-02-16 v1

Abstract

In this paper we consider combinatorial numbers Cm,kC_{m, k} for m1m\ge 1 and k0k\ge 0 which unifies the entries of the Catalan triangles Bn,k B_{n, k} and An,k A_{n, k} for appropriate values of parameters mm and kk, i.e., Bn,k=C2n,nkB_{n, k}=C_{2n,n-k} and An,k=C2n+1,n+1kA_{n, k}=C_{2n+1,n+1-k}. In fact, some of these numbers are the well-known Catalan numbers CnC_n that is C2n,n1=C2n+1,n=CnC_{2n,n-1}=C_{2n+1,n}=C_n. We present new identities for recurrence relations, linear sums and alternating sum of Cm,kC_{m,k}. After that, we check sums (and alternating sums) of squares and cubes of Cm,kC_{m,k} and, consequently, for Bn,k B_{n, k} and An,k A_{n, k}. In particular, one of these equalities solves an open problem posed in \cite{[GHMN]}. We also present some linear identities involving harmonic numbers HnH_n and Catalan triangles numbers Cm,kC_{m,k}. Finally, in the last section new open problems and identities involving CnC_n are conjectured.

Keywords

Cite

@article{arxiv.1602.04347,
  title  = {Sums of powers of Catalan triangle numbers},
  author = {Pedro J. Miana and Hideyuki Ohtsuka and Natalia Romero},
  journal= {arXiv preprint arXiv:1602.04347},
  year   = {2016}
}