In this article, we show that for any simple, bridgeless graph G on n vertices, there is a family C of at most n-1 cycles which cover the edges of G at least twice. A similar, dual result is also proven for cocycles namely: for any loopless graph G on n vertices and edges having cogirth g \* β₯ 3 and
Pentagons and cycle coverings
β Scribed by Hong Wang
- Publisher
- John Wiley and Sons
- Year
- 2007
- Tongue
- English
- Weight
- 190 KB
- Volume
- 54
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Abstract
Let G be a graph of order n β₯ 5__k__ + 2, where k is a positive integer. Suppose that the minimum degree of G is at least β(n + k)/2β. We show that G contains k pentagons and a path such that they are vertexβdisjoint and cover all the vertices of G. Moreover, if n β₯ 5__k__ + 7, then G contains k + 1 vertexβdisjoint cycles covering all the vertices of G such that k of them are pentagons. Β© 2006 Wiley Periodicals, Inc. J Graph Theory 54: 194β208, 2007
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