For positive integers ๐, ๐, ๐ with ๐ > ๐ , the set-coloring Ramsey number ๐ (๐; ๐, ๐ ) is the minimum ๐ such that if every edge of the complete graph ๐พ๐ receives a set of ๐ colors from a palette of ๐ colors, then there is guaranteed to be a monochromatic clique on ๐ vertices, that is, a subset of ๐ vertices where all of the edges between them receive a common color. In particular, the case ๐ = 1 corresponds to the classical multicolor Ramsey number. We prove general upper and lower bounds on ๐ (๐; ๐, ๐ ) which imply that ๐ (๐; ๐, ๐ ) = 2ฮ(๐๐) if ๐ /๐ is bounded away from 0 and 1. The upper bound extends an old result of Erdลs and Szemerรฉdi, who treated the case ๐ = ๐ โ 1, while the lower bound exploits a connection to error-correcting codes. We also study the analogous problem for hypergraphs.
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