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arXiv · 2002.11818

Finding large matchings in 1-planar graphs of minimum degree 3

Therese Biedl·Fabian Klute
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Abstract

A matching is a set of edges without common endpoint. It was recently shown that every 1-planar graph (i.e., a graph that can be drawn in the plane with at most one crossing per edge) that has minimum degree 3 has a matching of size at least $\frac{n+12}{7}$, and this is tight for some graphs. The proof did not come with an algorithm to find the matching more efficiently than a general-purpose maximum-matching algorithm. In this paper, we give such an algorithm. More generally, we show that any matching that has no augmenting paths of length 9 or less has size at least $\frac{n+12}{7}$ in a 1-planar graph with minimum degree 3.

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Therese Biedl, Fabian Klute. 2020-02-26. Finding large matchings in 1-planar graphs of minimum degree 3. https://arxiv.org/abs/2002.11818

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