ISSN 1234-3099 (print version)

ISSN 2083-5892 (electronic version)

Discussiones Mathematicae Graph Theory

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Discussiones Mathematicae Graph Theory


Discussiones Mathematicae Graph Theory  17(2) (1997)  301-309
DOI: 10.7151/dmgt.1057


Pranava K. Jha

Department of Computer Engineering
Delhi Institute of Technology: Delhi Kashmere Gate
Delhi 110 006, India


Sandi Klavžar
Blaž Zmazek

Department of Mathematics, PEF, University of Maribor
Koro ska cesta 160, 2000 Maribor, Slovenia



Weichsel (Proc. Amer. Math. Soc. 13 (1962) 47-52) proved that the Kronecker product of two connected bipartite graphs consists of two connected components. A condition on the factor graphs is presented which ensures that such components are isomorphic. It is demonstrated that several familiar and easily constructible graphs are amenable to that condition. A partial converse is proved for the above condition and it is conjectured that the converse is true in general.

Keywords: Kronecker product, bipartite graphs, graph isomorphism.

1991 Mathematics Subject Classification: 05C60.


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