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<record version="5" id="2940">
 <title>edge covering</title>
 <name>EdgeCovering</name>
 <created>2002-05-26 03:08:37</created>
 <modified>2002-07-06 13:48:36</modified>
 <type>Definition</type>
 <creator id="22" name="vampyr"/>
 <author id="22" name="vampyr"/>
 <classification>
	<category scheme="msc" code="05C70"/>
 </classification>
 <defines>
	<concept>minimal edge covering</concept>
 </defines>
 <related>
	<object name="Matching"/>
 </related>
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 <content>Let $G$ be a graph.  An \emph{edge covering} $C$ on $G$ is a subset of the vertices of $G$ such that each edge in $G$ is incident with at least one vertex in $C$.

For any graph, the \PMlinkescapeword{entire} vertex set is a trivial edge covering.  Generally, we are more interested in \emph{minimal coverings}.  A minimal edge covering is simply an edge covering of the least possible \PMlinkescapeword{size}.</content>
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