## Abstract In this paper we introduce a new class of directed graphs called locally semicomplete digraphs. These are defined to be those digraphs for which the following holds: for every vertex __x__ the vertices dominated by __x__ induce a semicomplete digraph and the vertices that dominate __x__
On a generalization of transitivity for digraphs
✍ Scribed by Andras Gyárfás; Michael S. Jacobson; Lael F. Kinch
- Publisher
- Elsevier Science
- Year
- 1988
- Tongue
- English
- Weight
- 758 KB
- Volume
- 69
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
✦ Synopsis
In this paper we investigate the foliowing generalization of transitivity: A digraph D is (m, n)-transitive whenever there is a path of length m from x to y there is a subset of n + 1 vertices of these m + 1 vertices which contain a path of length n from x to y.
Here we study various properties of (m, n)-transitive digraphs. In particular, (m, I)-transitive tournaments are characterized. Their similarities to transitive tournaments are analyzed and discussed.
Various other results pertaining to (m, I)-transitive digraphs are given.
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