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Source labels openChecked July 26, 2026

Erdős ProblemsCombinatorics

Erdős Problem 564

Let R3(n)R_3(n) be the minimal mm such that if the edges of the 33-uniform hypergraph on mm vertices are 22-coloured then there is a monochromatic copy of the complete 33-uniform hypergraph on nn vertices.

Mathematical statement

Let R3(n)R_3(n) be the minimal mm such that if the edges of the 33-uniform hypergraph on mm vertices are 22-coloured then there is a monochromatic copy of the complete 33-uniform hypergraph on nn vertices.

Is there some constant c>0c>0 such that R3(n)22cn?R_3(n) \geq 2^{2^{cn}}?

Statement source: Erdős Problems statement material

Statement terms: Source-specific

Source-specific terms. Therefore does not assert reuse rights beyond attributed display.

Statement artifacts, not proofs

These records expose exact Lean propositions and statement-only wrappers. Defining a proposition does not supply a proof of it. A placeholder-bearing target also contains no proof. Elaboration checks syntax and types; it does not certify that a formalization perfectly captures every nuance of the informal problem.

Pinned Lean formulation 1

erdos_564

Canonical source
Complete statement target, proof intentionally absentLean 4
theorem erdos_564 : answer(sorry)      c > 0, ᶠ n in atTop, (2 : )^(2 : )^(c * n)  hypergraphRamsey 3 n := by  sorry
Statement source
Formal Conjectures
Lean version
v4.27.0
Placeholder
Present; no proof artifact
Source evidence
Pinned source index
Fidelity review
Community formulation

References