Lagrangians of hypergraphs II: When colex is best
نویسندگان
چکیده
A well-known conjecture of Frankl and Füredi from 1989 states that an initial segment the colexicographic order has largest Lagrangian any r-uniform hypergraph with m hyperedges. We show this is true when r = 3. also give a new proof related Nikiforov for large t counterexample to old Ahlswede Katona.
منابع مشابه
Lagrangians Of Hypergraphs
How large can the Lagrangian of an r-graph with m edges be? Frankl and Füredi [1] conjectured that the r-graph of size m formed by taking the first m sets in the colex ordering of N(r) has the largest Lagrangian of all r-graphs of size m. We prove the first ‘interesting’ case of this conjecture, namely that the 3-graph with ( t 3 ) edges and largest Lagrangian is [t](3). We also prove that this...
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ژورنال
عنوان ژورنال: Israel Journal of Mathematics
سال: 2021
ISSN: ['1565-8511', '0021-2172']
DOI: https://doi.org/10.1007/s11856-021-2132-2