## Abstract The cyclic chromatic number of a plane graph __G__ is the smallest number Ο~__c__~(__G__) of colors that can be assigned to vertices of __G__ in such a way that whenever two distinct vertices are incident with a common face, they receive distinct colors. It was conjectured by Plummer an
A better bound for the cop number of general graphs
β Scribed by Ehsan Chiniforooshan
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 85 KB
- Volume
- 58
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
In this note, we prove that the cop number of any nβvertex graph G, denoted by ${{c}}({{G}})$, is at most ${{O}}\big({{{n}}\over {{\rm lg}} {{n}}}\big)$. Meyniel conjectured ${{c}}({{G}})={{O}}(\sqrt{{{n}}})$. It appears that the best previously known sublinear upperβbound is due to Frankl, who proved ${{c}}({{G}})\leq ({{1}}+ {{o}}({{1}})){{{n}}{{\rm lg}}{{\rm lg}} {{n}}\over {{\rm lg}} {{n}}}$. Β© 2008 Wiley Periodicals, Inc. J Graph Theory 58: 45β48, 2008
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