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On Point-Symmetric Tournaments

Published online by Cambridge University Press:  20 November 2018

Brian Alspach*
Affiliation:
Simon Fraser University, Burnaby, British Columbia
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A tournament is a directed graph in which there is exactly one arc between any two distinct vertices. Let denote the automorphism group of T. A tournament T is said to be point-symmetric if acts transitively on the vertices of T. Let g(n) be the maximum value of taken over all tournaments of order n. In [3] Goldberg and Moon conjectured that with equality holding if and only if n is a power of 3. The case of point-symmetric tournaments is what prevented them from proving their conjecture. In [2] the conjecture was proved through the use of a lengthy combinatorial argument involving the structure of point-symmetric tournaments. The results in this paper are an outgrowth of an attempt to characterize point-symmetric tournaments so as to simplify the proof employed in [2].

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1970

References

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