Erdős problem 1167
Erdős Problem 1167. Let be finite, , and be an infinite cardinal. Let be cardinals for all . Is it true that implies Here means cardinal addition, so that if is infinite.
Sources
FormalConjectures/ErdosProblems/
1167.lean
Retained formal statement
Erdős Problem 1167. Let be finite, , and be an infinite cardinal. Let be cardinals for all . Is it true that implies Here means cardinal addition, so that if is infinite.
A problem of Erdős, Hajnal, and Rado.
True ↔ ∀ (r : ℕ), 2 ≤ r → ∀ (lam : Cardinal.{u}), Cardinal.aleph0 ≤ lam → ∀ (γ : Ordinal.{u}), 2 ≤ γ → ∀ (κ : γ.ToType → Cardinal.{u}), (Combinatorics.cardinalPartitionRel (2 ^ lam) (r + 1) γ fun α => κ α + 1) → Combinatorics.cardinalPartitionRel lam r γ κOpenStatement only, no proof