Quasirandom permutations are characterized by 4-point densities
نویسندگان
چکیده
منابع مشابه
Quasirandom permutations are characterized by 4-point densities
For permutations π and τ of lengths |π| ≤ |τ |, let t(π, τ) be the probability that the restriction of τ to a random |π|-point set is (order) isomorphic to π. We show that every sequence {τj} of permutations such that |τj| → ∞ and t(π, τj) → 1/4! for every 4-point permutation π is quasirandom (that is, t(π, τj) → 1/|π|! for every π). This answers a question posed by Graham.
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ژورنال
عنوان ژورنال: Geometric and Functional Analysis
سال: 2013
ISSN: 1016-443X,1420-8970
DOI: 10.1007/s00039-013-0216-9