Vertices x and y dominate a tournament T if for all vertices z / = x, y, either x beats z or y beats z. Let dom(T ) be the graph on the vertices of T with edges between pairs of vertices that dominate T . We show that dom(T ) is either an odd cycle with possible pendant vertices or a forest of cater
Niche graphs and mixed pair graphs of tournaments
β Scribed by Bowser, Steve; Cable, Charles; Lundgren, Richard
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 339 KB
- Volume
- 31
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
In our efforts to study the niche graph of a tournament T , we have found it easier to study the complement, which we call the ''mixed pair'' graph of T and denote MP (T ). We show that an undirected graph G is MP (T ), for some tournament T , if and only if G is one of the following: a cycle of odd order, a path of even order, a forest of odd order consisting of two paths, a forest of even order consisting of three paths, or a forest of four or more paths. (In this description, we consider an isolated vertex to be a path.
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