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Erdős problem 70

Erdős Problem 70: Let c\mathfrak{c} be the cardinality of the continuum, let β\beta be a countable ordinal, and let 2≤n<ω2 \le n < \omega. Is it true that c→(β,n)23\mathfrak{c} \to (\beta, n)^3_2?

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70.lean

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Erdős Problem 70: Let c\mathfrak{c} be the cardinality of the continuum, let β\beta be a countable ordinal, and let 2≤n<ω2 \le n < \omega. Is it true that c→(β,n)23\mathfrak{c} \to (\beta, n)^3_2?

Note: The cases n≤3n \le 3 are trivially true (see omega_three), so the genuine content of the conjecture begins at n=4n = 4.

FormalConjectures/ErdosProblems/70.leanErdos70.erdos_703 linesExact file
True ↔  ∀ (β : Ordinal.{0}) (n : ℕ),    β.card ≤ Cardinal.aleph0 → 2 ≤ n → Erdos70.OrdinalCardinalRamsey3 Cardinal.continuum.ord β ↑n
OpenStatement only, no proof