Definition:Loop (Graph Theory)
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Definition
Let $G = \left({V, E}\right)$ be a loop-graph.
A loop is an edge $e$ of $G$ whose endvertices are the same vertex.
Thus if $e$ is a loop on the vertex $v$, it would be written $e = vv$.
Sources
- Gary Chartrand: Introductory Graph Theory (1977): $\S 1.6$
