Cycle-minors and subdivisions of wheels
β Scribed by Galen E. Turner III
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 130 KB
- Volume
- 62
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
In this paper we prove two results. The first is an extension of a result of Dirac which says that any set of n vertices of an nβconnected graph lies in a cycle. We prove that if Vβ² is a set of at most 2__n__ vertices in an nβconnected graph G, then G has, as a minor, a cycle using all of the vertices of Vβ². The second result says that if G is an n+1βconnected graph with maximum vertex degree Ξ then G contains a subgraph that is a subdivision of W~2__n__~ if and only if Ξβ₯2__n__. Β© 2009 Wiley Periodicals, Inc. J Graph Theory 62: 100β108, 2009
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