The minimum size of 3-graphs without a 4-set spanning no or exactly three edges
نویسنده
چکیده
Let Gi be the (unique) 3-graph with 4 vertices and i edges. Razborov [On 3Hypergraphs with Forbidden 4-Vertex Configurations, SIAM J. Discr. Math. 24 (2010), 946–963] determined asymptotically the minimum size of a 3-graph on n vertices having neither G0 nor G3 as an induced subgraph. Here we obtain the corresponding stability result, determine the extremal function exactly, and describe all extremal hypergraphs for n ≥ n0. It follows that any sequence of almost extremal hypergraphs converges, which answers in the affirmative a question posed by Razborov.
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ورودعنوان ژورنال:
- Eur. J. Comb.
دوره 32 شماره
صفحات -
تاریخ انتشار 2011