Erdős problem 591

Let $α$ be the infinite ordinal $\omega^{\omega^2}$ . Is it true that any red/blue colouring of the edges of $K_α$ there is either a red $K_α$ or a blue $K_3$ ?

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FormalConjectures/ErdosProblems/

591.lean

Retained formal statement1 of 1

Let $α$ be the infinite ordinal $\omega^{\omega^2}$ . Is it true that any red/blue colouring of the edges of $K_α$ there is either a red $K_α$ or a blue $K_3$ ?

This is true and was proved independently by Schipperus [Sc10] and Darby.

FormalConjectures/ErdosProblems/591.leanErdos591.erdos_5911 lineExact file

1True ↔ OrdinalCardinalRamsey (Ordinal.omega0 ^ Ordinal.omega0 ^ 2) (Ordinal.omega0 ^ Ordinal.omega0 ^ 2) 3

SolvedStatement only, no proof