In this paper we obtain two sufficient conditions, Ore type (Theorem 1) and Dirac type (Theorem 2). on the degrees of a bipartite oriented graph for ensuring the existence of long paths and cycles. These conditions are shown to be the best possible in a sense. An oriented graph is a digraph without
Parity theorems for paths and cycles in graphs
β Scribed by J. A. Bondy; F. Y. Halberstam
- Publisher
- John Wiley and Sons
- Year
- 1986
- Tongue
- English
- Weight
- 294 KB
- Volume
- 10
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
We extend an elegant proof technique of A . G . Thomason, and deduce several parity theorems for paths and cycles in graphs. For example, a graph in which each vertex is of even degree has an even number of paths if and only if it is of even order, and a graph in which each vertex is of odd degree has an even number of paths if and only if its order is a multiple of four. Our results have implications for generalized friendship graphs and their conjectured nonexistence.
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