English

Two integer sequences related to Catalan numbers

Combinatorics 2012-08-01 v4

Abstract

We prove the following conjecture of Zeilberger. Denoting by CnC_n the Catalan number, define inductively AnA_n by (1)n1An=Cn+j=1n1(1)j(2n12j1)AjCnj(-1)^{n-1}A_n=C_n+\sum_{j=1}^{n-1} (-1)^{j} \binom{2n-1}{2j-1} A_j \,C_{n-j} and an=2An/Cna_n=2A_n/C_n. Then ana_n (hence AnA_n) is a positive integer.

Keywords

Cite

@article{arxiv.1009.4225,
  title  = {Two integer sequences related to Catalan numbers},
  author = {Michel Lassalle},
  journal= {arXiv preprint arXiv:1009.4225},
  year   = {2012}
}

Comments

15 pages, LaTeX, to appear in Journal of Combinatorial Theory, Series A

R2 v1 2026-06-21T16:17:16.144Z