Isomorphic components of direct products of bipartite graphs

نویسنده

  • Richard Hammack
چکیده

A standard result states the direct product of two connected bipartite graphs has exactly two components. Jha, Klavžar and Zmazek proved that if one of the factors admits an automorphism that interchanges partite sets, then the components are isomorphic. They conjectured the converse to be true. We prove the converse holds if the factors are square-free. Further, we present a matrix-theoretic conjecture that, if proved, would prove the general case of the converse; if refuted, it would produce a counterexample.

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عنوان ژورنال:
  • Discussiones Mathematicae Graph Theory

دوره 26  شماره 

صفحات  -

تاریخ انتشار 2006