The odd-girth of a graph is the length of a shortest odd circuit. A conjecture by Pavol Hell about circular coloring is solved in this article by showing that there is a function f ( ) for each : 0 < < 1 such that, if the odd-girth of a planar graph G is at least f ( ), then G is (2 + )-colorable. N
Total Colourings of Planar Graphs with Large Girth
β Scribed by O.V. Borodin; A.V. Kostochka; D.R. Woodall
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 96 KB
- Volume
- 19
- Category
- Article
- ISSN
- 0195-6698
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β¦ Synopsis
It is proved that if G is a planar graph with total (vertex-edge) chromatic number Ο , maximum degree and girth g, then Ο = + 1 if β₯ 5 and g β₯ 5, or β₯ 4 and g β₯ 6, or β₯ 3 and g β₯ 10. These results hold also for graphs in the projective plane, torus and Klein bottle.
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