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تسجيل مستخدم جديدStability theorems for some Kruskal-Katona type results
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The classical Kruskal-Katona theorem gives a tight upper bound for the size of an $r$-uniform hypergraph $mathcal{H}$ as a function of the size of its shadow. Its stability version was obtained by Keevash who proved that if the size of $mathcal{H}$ is close to the maximum, then $mathcal{H}$ is structurally close to a complete $r$-uniform hypergraph. We prove similar stability results for two classes of hypergraphs whose extremal properties have been investigated by many researchers: the cancellative hypergraphs and hypergraphs without expansion of cliques.
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