{ "id": "2207.03747", "version": "v1", "published": "2022-07-08T08:32:13.000Z", "updated": "2022-07-08T08:32:13.000Z", "title": "On the size of matchings in 1-planar graph with high minimum degree", "authors": [ "Yuanqiu Huang", "Zhangdong Ouyang", "Fengming Dong" ], "comment": "19 pages and 5 figures. To appear in SIAM Discrete Mathematics", "categories": [ "math.CO" ], "abstract": "A matching of a graph is a set of edges without common end vertex. A graph is called 1-planar if it admits a drawing in the plane such that each edge is crossed at most once. Recently, Biedl and Wittnebel proved that every 1-planar graph with minimum degree 3 and $n\\geq 7$ vertices has a matching of size at least $\\frac{n+12}{7}$, which is tight for some graphs. They also provided tight lower bounds for the sizes of matchings in 1-planar graphs with minimum degree 4 or 5. In this paper, we show that any 1-planar graph with minimum degree 6 and $n \\geq 36$ vertices has a matching of size at least $\\frac{3n+4}{7}$, and this lower bound is tight. Our result confirms a conjecture posed by Biedl and Wittnebel.", "revisions": [ { "version": "v1", "updated": "2022-07-08T08:32:13.000Z" } ], "analyses": { "subjects": [ "05C10", "05C35", "05C70" ], "keywords": [ "high minimum degree", "tight lower bounds", "common end vertex", "result confirms" ], "note": { "typesetting": "TeX", "pages": 19, "language": "en", "license": "arXiv", "status": "editable" } } }