English

Matchings in 1-planar graphs with large minimum degree

Discrete Mathematics 2020-02-21 v2 Combinatorics

Abstract

In 1979, Nishizeki and Baybars showed that every planar graph with minimum degree 3 has a matching of size n3+c\frac{n}{3}+c (where the constant cc depends on the connectivity), and even better bounds hold for planar graphs with minimum degree 4 and 5. In this paper, we investigate similar matching-bounds for {\em 1-planar} graphs, i.e., graphs that can be drawn such that every edge has at most one crossing. We show that every 1-planar graph with minimum degree 3 has a matching of size at least 17n+127\frac{1}{7}n+\frac{12}{7}, and this is tight for some graphs. We provide similar bounds for 1-planar graphs with minimum degree 4 and 5, while the case of minimum degree 6 and 7 remains open.

Keywords

Cite

@article{arxiv.1911.04603,
  title  = {Matchings in 1-planar graphs with large minimum degree},
  author = {Therese Biedl and John Wittnebel},
  journal= {arXiv preprint arXiv:1911.04603},
  year   = {2020}
}
R2 v1 2026-06-23T12:12:26.516Z