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
The Odd Girth of the Generalised Kneser Graph
β Scribed by Tristan Denley
- Publisher
- Elsevier Science
- Year
- 1997
- Tongue
- English
- Weight
- 202 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0195-6698
No coin nor oath required. For personal study only.
β¦ Synopsis
Let X Ο Ν 1 , 2 , . . . , n Ν be a set of n elements and let X ( r ) be the collection of all the subsets of X containing precisely r elements . Then the generalised Kneser graph K ( n , r , s ) (when 2 r Οͺ s Ρ n ) is the graph with vertex set X ( r ) and edges AB for A , B X ( r ) with Ν A Κ B Ν Ρ s .
Here we show that the odd girth of the generalised Kneser graph
provided that n is large enough compared with r and s .
π SIMILAR VOLUMES
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