Triple systems for identifying quadruples
نویسنده
چکیده
A collectionC of distinct 3-element subsets of the set S = {1, 2, . . . , n} is called an identifying system of the quadruples of S, if every 4-element subset of S contains at least one of the triples in C, and moreover, no two 4-element subsets of S contain exactly the same triples of C. We consider the minimal possible cardinality of such a system, and show, in particular, that for n = 6, 7 and 8, the minimal cardinalities are 8, 14 and 26, respectively.
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عنوان ژورنال:
- Australasian J. Combinatorics
دوره 25 شماره
صفحات -
تاریخ انتشار 2002