Bondy and Vince proved that every graph with minimum degree at least three contains two cycles whose lengths differ by one or two, which answers a question raised by Erdo Λs. By a different approach, we show in this paper that if G is a graph with minimum degree d(G) \ 3k for any positive integer k,
Unavoidable cycle lengths in graphs
β Scribed by Jacques Verstraete
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 160 KB
- Volume
- 49
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
An old conjecture of ErdΕs states that there exists an absolute constant c and a set S of density zero such that every graph of average degree at least c contains a cycle of length in S. In this paper, we prove this conjecture by showing that every graph of average degree at least ten contains a cycle of length in a prescribed set S satisfying $|S \cap { 1,2,\ldots ,n} | = O(n^{0.99})$. Β© 2005 Wiley Periodicals, Inc. J Graph Theory
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