Let F be a graph.A hypergraph H is called a Berge-F if there is a bijection φ:E(F)→ E(H)such that e C φ(e)for each e ∈ E(F).We say that the hypergraph H is Berge-F-free if there is no sub-hypergraph of H isomorphic to any Berge-F.The maximum number of edges,denoted by exr(n,Berge-F),in an n-vertex r-uniform Berge-F-free hypergraph is the Turán number of Berge-F.A graph F is called an edge-critical graph if the removal of an edge decreases the chromatic number of F.In this paper,we give the Turán number of Berge-F when F is pKk or an edge-critical graph.
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