ArticleOriginal scientific text

Title

Towards a characterization of bipartite switching classes by means of forbidden subgraphs

Authors 1, 2

Affiliations

  1. Department of Information, and Computing Sciences, University Utrecht, P.O. Box 80.089, 3508 TB Utrecht, Netherlands
  2. Department of Mathematics, University of Turku, FIN-20014 Turku, Finland

Abstract

We investigate which switching classes do not contain a bipartite graph. Our final aim is a characterization by means of a set of critically non-bipartite graphs: they do not have a bipartite switch, but every induced proper subgraph does. In addition to the odd cycles, we list a number of exceptional cases and prove that these are indeed critically non-bipartite. Finally, we give a number of structural results towards proving the fact that we have indeed found them all. The search for critically non-bipartite graphs was done using software written in C and Scheme. We report on our experiences in coping with the combinatorial explosion.

Keywords

switching classes, bipartite graphs, forbidden subgraphs, combinatorial search

Bibliography

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Pages:
471-483
Main language of publication
English
Received
2006-05-19
Accepted
2007-06-13
Published
2007
Exact and natural sciences