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arXiv · 1009.4225

Two integer sequences related to Catalan numbers

Michel Lassalle
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Abstract

We prove the following conjecture of Zeilberger. Denoting by $C_n$ the Catalan number, define inductively $A_n$ by $(-1)^{n-1}A_n=C_n+\sum_{j=1}^{n-1} (-1)^{j} \binom{2n-1}{2j-1} A_j \,C_{n-j}$ and $a_n=2A_n/C_n$. Then $a_n$ (hence $A_n$) is a positive integer.

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Michel Lassalle. 2012-01-10. Two integer sequences related to Catalan numbers. https://arxiv.org/abs/1009.4225

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