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Directed packings of pairs into quadruples

Published online by Cambridge University Press:  09 April 2009

David B. Skillicorn
Affiliation:
Department of Mathematics, Statistics and Computing ScienceDalhousie University Halifax, Nova Scotia B3H 4H8, Canada
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Abstract

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A directed packing of pairs into quadruples is a collection of 4-subsets of a set of cardinality ν with the property that each ordered pair of elements appears at most once in a 4-subset (or block). The maximal number of blocks with this property is denoted by DD(2, 4, ν). Such a directed packing may also be thought of as a packing of transtivie tournaments into the complete directed graph on ν points. It is shown that, for all but a finite number of values of ν, DD(2, 4, ν) is maximal.

MSC classification

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 1982

References

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