Some bicyclic antiautomorphisms of directed triple systems

نویسندگان

  • Neil P. Carnes
  • Anne Dye
  • James F. Reed
چکیده

A transitive triple, (a, b, c), is defined to be the set {(a, b), (b, c), (a, c)} of ordered pairs. A directed triple system of order v, DTS(v), is a pair (D, β), where D is a set of v points and β is a collection of transitive triples of pairwise distinct points of D such that any ordered pair of distinct points of D is contained in precisely one transitive triple of β. An antiautomorphism of a directed triple system, (D, β), is a permutation of D which maps β to β−1, where β−1 = {(c, b, a) | (a, b, c) ∈ β}. In this paper we give necessary and sufficient conditions for the existence of a directed triple system of order v admitting an antiautomorphism consisting of two cycles, where one cycle is twice the length of the other.

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عنوان ژورنال:
  • Australasian J. Combinatorics

دوره 28  شماره 

صفحات  -

تاریخ انتشار 2003