Signed analogs of bipartite graphs 1
نویسنده
چکیده
We characterize the edge-signed graphs in which every 'significant' positive closed walk (or combination of walks) has even length, under seven different criteria for significance, and also those edge-signed graphs whose double covering graph is bipartite. If the property of even length is generalized to positivity in a second edge signing, the characterizations generalize as well. We also characterize the edge-signed graphs with the smallest nontrivial chromatic numbers.
منابع مشابه
Signed analogs of bipartite graphs
Thomas Zaslavsky Binghamton University Binghamton, New York, U.S.A. 13902-6000 September 1991 Revised July 1996 Abstra t We hara terize the edge-signed graphs in whi h every \signi ant" positive losed walk (or ombination of walks) has even length, under seven di erent riteria for signi an e, and also those edge-signed graphs whose double overing graph is bipartite. If the property of even lengt...
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