Circuit decompositions of join-covered graphs
✍ Scribed by Marcelo H. de Carvalho; C. H. C. Little
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 137 KB
- Volume
- 62
- Category
- Article
- ISSN
- 0364-9024
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✦ Synopsis
Abstract
In this paper, we focus our attention on join‐covered graphs, that is, ±1‐weighted graphs, without negative circuits, in which every edge lies in a zero‐weight circuit. Join covered graphs are a natural generalization of matching‐covered graphs. Many important properties of matching covered graphs, such as the existence of a canonical partition, tight cut decomposition and ear decomposition, have been generalized to join covered graphs by A. Sebő [5]. In this paper we prove that any two edges of a join‐covered graph lie on a zero‐weight circuit (under an equivalent weighting), generalize this statement to an arbitrary number of edges, and characterize minimal bipartite join‐covered graphs. © 2009 Wiley Periodicals, Inc. J Graph Theory 62, 220–233, 2009
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