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Erdős problem 20

Is it true that f(n,k)<cknf(n,k) < c_k^n for some constant ck>0c_k>0 and for all n>0n > 0?

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3 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

20.lean

Retained formal statement2 of 3

Erdős and Rado [ErRa60] proved the factorial upper bound for the kk-sunflower threshold: any family of nn-uniform sets with more than (k−1)n n!(k-1)^n \, n! members contains a kk-sunflower, hence f(n,k)≤(k−1)n n!+1f(n,k) \le (k-1)^n \, n! + 1.

FormalConjectures/ErdosProblems/20.leanErdos20.erdos_20.variants.erdos_rado_bound1 lineExact file
∀ (n k : ℕ), n > 0 → 2 ≤ k → Erdos20.f n k ≤ (k - 1) ^ n * n.factorial + 1
SolvedStatement only, no proof