A note on the uniformity threshold for Berge hypergraphs
نویسندگان
چکیده
A Berge copy of a graph is hypergraph obtained by enlarging the edges arbitrarily. Grósz, Methuku and Tompkins in 2020 showed that for any F, there an integer r0=r0(F), such r?r0, r-uniform without F has o(n2) hyperedges. The smallest r0 called uniformity threshold denoted th(F). They th(F)?R(F,F?), where R denotes off-diagonal Ramsey number F? form deleting edge. We improve this bound to th(F)?R(K?(F),F?), use new determine th(F) exactly several classes graphs.
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ژورنال
عنوان ژورنال: European Journal of Combinatorics
سال: 2022
ISSN: ['1095-9971', '0195-6698']
DOI: https://doi.org/10.1016/j.ejc.2022.103561