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Erdős problem 598

Erdős Problem 598: Let mm be an infinite cardinal and κ\kappa be the successor cardinal of 2ℵ02^{\aleph_0}. Can one colour the countable subsets of mm using κ\kappa many colours so that every X⊆mX \subseteq m with ∣X∣=κ|X| = \kappa contains subsets of all possible colours?

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FormalConjectures/ErdosProblems/

598.lean

Retained formal statement1 of 1

Erdős Problem 598: Let mm be an infinite cardinal and κ\kappa be the successor cardinal of 2ℵ02^{\aleph_0}. Can one colour the countable subsets of mm using κ\kappa many colours so that every X⊆mX \subseteq m with ∣X∣=κ|X| = \kappa contains subsets of all possible colours?

FormalConjectures/ErdosProblems/598.leanErdos598.erdos_5981 lineExact file
∀ (m : Type u_1) [Infinite m], True ↔ ∃ c, ∀ (X : Set m), Cardinal.mk ↑X = Erdos598.κ → c '' {s | ↑s ⊆ X} = Set.univ
OpenStatement only, no proof