We show that if G is a 3-connected graph of order at least seven, then every longest path between distinct vertices in G contains at least two contractible edges. An immediate corollary is that longest cycles in such graphs contain at least three contractible edges. We consider only finite undirect
A degree sum condition for longest cycles in 3-connected graphs
β Scribed by Tomoki Yamashita
- Publisher
- John Wiley and Sons
- Year
- 2007
- Tongue
- English
- Weight
- 110 KB
- Volume
- 54
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Abstract
For a graph G, we denote by d~G~(x) and ΞΊ(G) the degree of a vertex x in G and the connectivity of G, respectively. In this article, we show that if G is a 3βconnected graph of order n such that d~G~(x) + d~G~(y) + d~G~(z) β₯ d for every independent set {x, y, z}, then G contains a cycle of length at least min{d β ΞΊ(G), n}. Β© 2006 Wiley Periodicals, Inc. J Graph Theory 54: 277β283, 2007
π SIMILAR VOLUMES
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