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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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6 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

70.lean

Retained formal statement2 of 6

Erdős–Rado partial result: c→(ω+n,4)23\mathfrak{c} \to (\omega + n, 4)^3_2 for any 2≤n<ω2 \le n < \omega. Positive partial answer to Problem 70 with β=ω+n\beta = \omega + n and the blue side fixed at 44.

FormalConjectures/ErdosProblems/70.leanErdos70.erdos_70.variants.erdos_rado1 lineExact file
∀ (n : ℕ), 2 ≤ n → Erdos70.OrdinalCardinalRamsey3 Cardinal.continuum.ord (Ordinal.omega0 + ↑n) 4
SolvedStatement only, no proof