Unavoidable Hypergraphs
نویسندگان
چکیده
The following very natural problem was raised by Chung and Erd\H{o}s in the early 80's has since been repeated a number of times. What is minimum Tur\'an $\text{ex}(n,\mathcal{H})$ among all $r$-graphs $\mathcal{H}$ with fixed edges? Their actual focus on an equivalent perhaps even more question which asks what largest size $r$-graph that can not be avoided any $n$ vertices $e$ In original paper they resolve this asymptotically for graphs, most range $e$. follow-up work $3$-uniform case raise $4$-uniform as next step. we make first progress over 40 years resolving gives us some indication how answer should behave general.
منابع مشابه
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A r-uniform hypergraph H (or a r-graph, for short) is a collection E= E(H) of r-element subsets (called edges) of a set V = V(H) (called vertices) . We say a r-graph H is (n, e)-unavoidable if every r-graph with n vertices and e edges must contain H . In this paper we investigate the largest possible number of edges in an (n, e)-unavoidable 3-graph for fixed n and e. We also study the structure...
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ژورنال
عنوان ژورنال: Trends in mathematics
سال: 2021
ISSN: ['2297-024X', '2297-0215']
DOI: https://doi.org/10.1007/978-3-030-83823-2_53