A note on lower bounds for hypergraph Ramsey numbers
نویسنده
چکیده
We improve upon the lower bound for 3-colour hypergraph Ramsey numbers, showing, in the 3-uniform case, that r3(l, l, l) ≥ 2 c log log l . The old bound, due to Erdős and Hajnal, was r3(l, l, l) ≥ 2 2 log2 .
منابع مشابه
New lower bounds for hypergraph Ramsey numbers
The Ramsey number rk(s, n) is the minimum N such that for every red-blue coloring of the k-tuples of {1, . . . , N}, there are s integers such that every k-tuple among them is red, or n integers such that every k-tuple among them is blue. We prove the following new lower bounds for 4-uniform hypergraph Ramsey numbers: r4(5, n) > 2 n log n and r4(6, n) > 2 2 1/5 , where c is an absolute positive...
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