A graph G is called k-choosable if k is a number such that if we give lists of k colors to each vertex of G there is a vertex coloring of G where each vertex receives a color from its own list no matter what the lists are. In this paper, it is shown that each plane graph without 4-cycles is 4-choosa
Coupled choosability of plane graphs
β Scribed by Weifan Wang; Ko-Wei Lih
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 197 KB
- Volume
- 58
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
A plane graph G is coupled kβchoosable if, for any list assignment L satisfying $|{{L}}({{x}})|= {{k}}$ for every ${{x}}\in {{V}}({{G}})\cup {{F}}({{G}})$, there is a coloring that assigns to each vertex and each face a color from its list such that any two adjacent or incident elements receive distinct colors. We prove that every plane graph is coupled 7βchoosable. We further show that maximal plane graphs, ${{K}}_{{4}}$βminor free graphs, and plane graphs with maximum degree at most three are coupled 6βchoosable. Β© 2008 Wiley Periodicals, Inc. J Graph Theory 58: 27β44, 2008
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