Graph Factor
A 1-factor of a graph G with n graph vertices is a set of n/2 separate graph edges which collectively contain all n of the graph vertices of G among their endpoints.
See also
GraphExplore with Wolfram|Alpha
WolframAlpha
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Cite this as:
Weisstein, Eric W. "Graph Factor." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/GraphFactor.html