منابع مشابه
Supersaturation for hereditary properties
Let F be a collection of r-uniform hypergraphs, and let 0 < p < 1. It is known that there exists c = c(p,F) such that the probability of a random r-graph in G(n, p) not containing an induced subgraph from F is 2(−c+o(1))( n r). Let each r-graph in F have at least t vertices. We show that in fact for every > 0, there exists δ = δ( , p,F) > 0 such that the probability of a random r-graph in G(n, ...
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Let A be a Banach algebra. A is called ideally amenable if for every closed ideal I of A, the first cohomology group of A with coefficients in I* is trivial. We investigate the closed ideals I for which H1 (A,I* )={0}, whenever A is weakly amenable or a biflat Banach algebra. Also we give some hereditary properties of ideal amenability.
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Let P be a hereditary property of words, i.e., an infinite class of finite words such that every subword (block) of a word belonging to P is also in P . Extending the classical Morse-Hedlund theorem, we show that either P contains at least n+1 words of length n for every n or, for some N , it contains at most N words of length n for every n. More importantly, we prove the following quantitative...
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2012
ISSN: 0195-6698
DOI: 10.1016/j.ejc.2011.10.008