ArticleOriginal scientific text
Title
On local structure of 1-planar graphs of minimum degree 5 and girth 4
Authors 1, 1
Affiliations
- Institute of Mathematics, Faculty of Sciences, University of P. J. Šafárik, Jesenná 5, 040 01 Košice, Slovak Republic
Abstract
A graph is 1-planar if it can be embedded in the plane so that each edge is crossed by at most one other edge. We prove that each 1-planar graph of minimum degree 5 and girth 4 contains (1) a 5-vertex adjacent to an ≤ 6-vertex, (2) a 4-cycle whose every vertex has degree at most 9, (3) a with all vertices having degree at most 11.
Keywords
light graph, 1-planar graph, star, cycle
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