Intersecting families of permutations and partial permutations
نویسندگان
چکیده
The above result motivated the study of intersecting families of permutations which was initiated by Deza and Frankl, see [2]. Let Sn be the symmetric group on [n], that is the group of all permutations of [n]. For a positive integer t, a subset A of Sn is said to be t-intersecting if, for any g, h ∈ A with g 6= h, we have |{x : g(x) = h(x)}| ≥ t. By an intersecting family, we mean an 1-intersecting set of permutations. Denote by α(n, t) the maximum cardinality of an t-intersecting family of Sn. Comparatively little is known about the number α(n, t) even though the analogous problem for subsets of a finite set has been widely studied: see [3] for a survey. The following result is the starting point of my research.
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