On conjectures of Frankl and El-Zahar
✍ Scribed by Bernardo Llano; Juan José Montellano-Ballesteros; Eduardo Rivera-Campo; Ricardo Strausz
- Book ID
- 102345587
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 135 KB
- Volume
- 57
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
An induced subgraph ${\cal S}$ of a graph ${\cal G}$ is called a derived subgraph of ${\cal G}$ if ${\cal S}$ contains no isolated vertices. An edge e of ${\cal S}$ is said to be residual if e occurs in more than half of the derived subgraphs of ${\cal S}$. In this article, we prove that every simple graph with at least one edge contains a non‐residual edge. This was conjectured by El‐Zahar in 1997. © 2008 Wiley Periodicals, Inc. J Graph Theory 57: 344–352, 2008
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