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Erdős problem 835

Does there exist a k>2k>2 such that the kk-sized subsets of {1,...,2k} can be coloured with k+1k+1 colours such that for every A⊂{1,…,2k}A\subset \{1,\ldots,2k\} with ∣A∣=k+1\lvert A\rvert=k+1 all k+1k+1 colours appear among the kk-sized subsets of AA?

Sources

The source's own material, retained exactly.

13 retained statements36c6d0fef71a

Open selected source

FormalConjectures/ErdosProblems/

835.lean

Retained formal statement12 of 13

Ma and Tang's result implies the cases for odd kk.

FormalConjectures/ErdosProblems/835.leanErdos835.johnsonGraph_chromaticNumber_odd_of_johnson_chromaticNumber_composite2 linesExact file
(∀ (k : ℕ), 2 < k → (k + 1).Composite → ↑k + 1 < (SimpleGraph.johnson (2 * k) k).chromaticNumber) →  ∀ (k : ℕ), 2 < k → Odd k → ↑k + 1 < (SimpleGraph.johnson (2 * k) k).chromaticNumber
TestStatement only, no proof