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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

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✦ 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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