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arXiv · 0803.0848

Asymptotic analysis of $k$-noncrossing matchings

Emma Y. Jin·Christian M. Reidys·Rita R. Wang
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Abstract

In this paper we study $k$-noncrossing matchings. A $k$-noncrossing matching is a labeled graph with vertex set $\{1,...,2n\}$ arranged in increasing order in a horizontal line and vertex-degree 1. The $n$ arcs are drawn in the upper halfplane subject to the condition that there exist no $k$ arcs that mutually intersect. We derive: (a) for arbitrary $k$, an asymptotic approximation of the exponential generating function of $k$-noncrossing matchings $F_k(z)$. (b) the asymptotic formula for the number of $k$-noncrossing matchings $f_{k}(n) \sim c_k n^{-((k-1)^2+(k-1)/2)} (2(k-1))^{2n}$ for some $c_k>0$.

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Emma Y. Jin, Christian M. Reidys, Rita R. Wang. 2008-03-06. Asymptotic analysis of $k$-noncrossing matchings. https://arxiv.org/abs/0803.0848

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