Erdős problem 212
Is there a dense subset of ℝ^2 such that all pairwise distances are rational?
Sources
FormalConjectures/ErdosProblems/
212.lean
Retained formal statement
Is there a dense subset of ℝ^2 such that all pairwise distances are rational?
True ↔ ∃ u, Dense u ∧ u.Pairwise fun c₁ c₂ => dist c₁ c₂ ∈ Set.range Rat.castOpenStatement only, no proof