A cyclic coloration of a planar graph G is an assignment of colors to the points of G such that for any face bounding cycle the points of f have different colors. We observe that the upper bound 2p\*(G), due to 0. Ore and M. D. Plummer, can be improved to p \* ( G ) + 9 when G is 3connected (p\* den
Cyclic degree and cyclic coloring of 3-polytopes
β Scribed by Borodin, Oleg V.
- Publisher
- John Wiley and Sons
- Year
- 1996
- Tongue
- English
- Weight
- 402 KB
- Volume
- 23
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
A vertex coloring of a plane graph is called cyclic if the vertices in each face bounding cycle are colored differently. The main result is an improvement of the upper bound for the cyclic chromatic number of 3-polytopes due to Plummer and Toft, 1987 (J. Graph Theory 11 (1 987) 505-51 7). The proof is based on a structural property of 3-polytopes, in a sense stronger than that implied by Lebesgue's theorem of 1940. Namely, precise upper bound is obtained for the minimum cyclic degree of 3-polytopes with the maximum face Size at least 24.
π SIMILAR VOLUMES
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