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arXiv · 1912.00555

Some Properties and Combinatorial Implications of Weighted Small Schr\"oder Numbers

Yu Hin Au
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Abstract

The $n^{\text{th}}$ small Schr\"oder number is $s(n) = \sum_{k \geq 0} s(n,k)$, where $s(n,k)$ denotes the number of plane rooted trees with $n$ leaves and $k$ internal nodes that each has at least two children. In this manuscript, we focus on the weighted small Schr\"oder numbers $s_d(n) = \sum_{k \geq 0} s(n,k) d^k$, where $d$ is an arbitrary fixed real number. We provide recursive and asymptotic formulas for $s_d(n)$, as well as some identities and combinatorial interpretations for these numbers. We also establish connections between $s_d(n)$ and several families of Dyck paths.

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Yu Hin Au. 2019-12-02. Some Properties and Combinatorial Implications of Weighted Small Schr\"oder Numbers. https://arxiv.org/abs/1912.00555

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