We show that in any n-partite tournament, where n/> 3, with no transmitters and no 3-kings, the number of 4-kings is at least eight. All n-partite tournaments, where n/>3, having eight 4-kings and no 3-kings are completely characterized. This solves the problem proposed in Koh and Tan (accepted).
Kings in multipartite tournaments
β Scribed by K.M. Koh; B.P. Tan
- Publisher
- Elsevier Science
- Year
- 1995
- Tongue
- English
- Weight
- 584 KB
- Volume
- 147
- Category
- Article
- ISSN
- 0012-365X
No coin nor oath required. For personal study only.
β¦ Synopsis
Let T be an n-partite tournament and let k,(T) denote the number of r-kings of T. Gutin (1986) and Petrovic and Thomassen (1991) proved independently that if T contains at most one transmitter, then k4(T) >i 1, and found infinitely many bipartite tournaments T with at most one transmitter such that k 3 (T) = 0. In this paper, we (i) obtain some sufficient conditions for Tto have k3(T )/> 1, (ii) show that if Tcontains no transmitter, then k4(T ) >/4 when n = 2, and k4(T ) >/3 when n >/3, and (iii) characterize all Twith no transmitter such that the equalities in (ii) hold.
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