A general upper bound for the cyclic chromatic number of 3-connected plane graphs
✍ Scribed by Hikoe Enomoto; Mirko Horňák
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 457 KB
- Volume
- 62
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
The cyclic chromatic number of a plane graph G is the smallest number χ~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 and Toft in 1987 that, for every 3‐connected plane graph G, χ~c~(G)≤Δ^*^(G) + 2, where Δ^*^(G) is the maximum face degree of G. The best upper bound known so far was Δ^*^(G) + 8. In the paper this bound is improved to Δ^*^(G) + 5. © 2009 Wiley Periodicals, Inc. J Graph Theory 62: 1–25, 2009
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