Median and quasi-median direct products of graphs
نویسندگان
چکیده
Median graphs are characterized among direct products of graphs on at least three vertices. Beside some trivial cases, it is shown that one component of G × P3 is median if and only if G is a tree in that the distance between any two vertices of degree at least 3 is even. In addition, some partial results considering median graphs of the form G ×K2 are proved, and it is shown that the only nonbipartite quasimedian direct product is K3 ×K3.
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ورودعنوان ژورنال:
- Discussiones Mathematicae Graph Theory
دوره 25 شماره
صفحات -
تاریخ انتشار 2005