ArticleOriginal scientific text
Title
Short cycles of low weight in normal plane maps with minimum degree 5
Authors 1, 2
Affiliations
- Novosibirsk State University, Siberian Branch, Russian Academy of Sciences, Novosibirsk, 630090, Russia
- Department of Mathematics, University of Nottingham, Nottingham, NG7 2RD, England
Abstract
In this note, precise upper bounds are determined for the minimum degree-sum of the vertices of a 4-cycle and a 5-cycle in a plane triangulation with minimum degree 5: w(C₄) ≤ 25 and w(C₅) ≤ 30. These hold because a normal plane map with minimum degree 5 must contain a 4-star with . These results answer a question posed by Kotzig in 1979 and recent questions of Jendrol' and Madaras.
Keywords
planar graphs, plane triangulation
Bibliography
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- A. Kotzig, From the theory of eulerian polyhedra, Mat. Cas. 13 (1963) 20-34. (in Russian)
- A. Kotzig, Extremal polyhedral graphs, Ann. New York Acad. Sci. 319 (1979) 569-570.