Let \_(n, m, k) be the largest number \_ # [0, 1] such that any graph on n vertices with independence number at most m has a subgraph on k vertices with at lest \_ } ( k 2 ) edges. Up to a constant multiplicative factor, we determine \_(n, m, k) for all n, m, k. For log n m=k n, our result gives \_(
On the independence ratio of a graph
β Scribed by Michael O. Albertson; Joan P. Hutchinson
- Publisher
- John Wiley and Sons
- Year
- 1978
- Tongue
- English
- Weight
- 318 KB
- Volume
- 2
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
This paper presents some recent results on lower bounds for independence ratios of graphs of positive genus and shows that in a limiting sense these graphs have the same independence ratios as do planar graphs. This last result is obtained by an application of Menger's Theorem to show that every triangulation of a surface of positive genus has a short cycle which does not separate the graph and is nonβcontractible on that surface.
π SIMILAR VOLUMES
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