Acyclicity of Switching Classes
β Scribed by J. Hage; T. Harju
- Publisher
- Elsevier Science
- Year
- 1998
- Tongue
- English
- Weight
- 133 KB
- Volume
- 19
- Category
- Article
- ISSN
- 0195-6698
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β¦ Synopsis
For a finite undirected graph G = (V, E) and a subset A β V , the vertex switching of G by A is defined as the graph G A = (V, E ), which is obtained from G by removing all edges between A and its complement A and adding as edges all nonedges between A and A. The switching class [G] determined by G consists of all vertex switchings G A for subsets A β V . We prove that the trees of a switching class [G] are isomorphic to each other. We also determine the types of trees T that have isomorphic copies in [G]. Finally we show that apart from one exceptional type of forest, the real forests in a switching class are isomorphic. Here a forest is real, if it is disconnected.
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