Let $α$ be the infinite ordinal $ω^{ω}$ . Is it true that in any red/blue colouring of the edges of $K_{α}$ there is either a red $K_{α}$ or a blue $K_{3}$ ?

Worked, still open.

set theory · solved · prize $250 · formalized (Lean) · 0 attempts

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AMS 3 · solved (literature)

theorem erdos_590 : OrdinalCardinalRamsey (ω ^ ω) (ω ^ ω) 3

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