On an adjacency property of almost all tournaments
نویسندگان
چکیده
منابع مشابه
On an adjacency property of almost all tournaments
Let n be a positive integer. A tournament is called nexistentially closed (or n-e.c.) if for every subset S of n vertices and for every subset T of S, there is a vertex x / ∈ S which is directed toward every vertex in T and directed away from every vertex in S\T. We prove that there is a 2-e.c. tournament with k vertices if and only if k ≥ 7 and k 6= 8, and give explicit examples for all such o...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 2006
ISSN: 0012-365X
DOI: 10.1016/j.disc.2005.12.030