Transitive partitions in realizations of tournament score sequences
β Scribed by Arthur H. Busch; Guantao Chen; Michael S. Jacobson
- Publisher
- John Wiley and Sons
- Year
- 2009
- Tongue
- English
- Weight
- 121 KB
- Volume
- 64
- Category
- Article
- ISSN
- 0364-9024
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
A tournament is an oriented complete graph, and one containing no
directed cycles is called transitive. A tournament
T=(V, A) is called mβpartition
transitive if there is a partition
such that the subtournaments induced by each X~i~ are all transitive, and T is mβpartition kβtransitive if max|X~i~|=k. Two tournaments are equivalent if they have the same outβdegree sequence. We show that for any m and k, T is equivalent to an mβpartition kβtransitive tournament Tβ² whenever T is equivalent to any tournament which contains a transitive subtournament of order at least k. This generalizes results of Guiduli et al. and Acosta et al., who proved the claim for m=2 and k=βn/2β, and m>2 and kβ©½βn/2β, respectively. Β© 2009 Wiley Periodicals, Inc. J Graph Theory 64: 52β62, 2010
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