Erdős problem 158
Let A be an infinite B₂[2] set. Must liminf |A ∩ {1, ..., N}| * N ^ (- 1 / 2) = 0?
Sources
FormalConjectures/ErdosProblems/
158.lean
Retained formal statement
Let A be an infinite Sidon set. Then liminf |A ∩ {1, ..., N}| * N ^ (- 1 / 2) * (log N) ^ (1 / 2) < ∞. This is proved in [ESS94].
∀ {A : Set ℕ}, A.Infinite → IsSidon A → Filter.liminf (fun N => ENNReal.ofReal (↑(A ∩ Set.Iio N).ncard * ↑N ^ (-1 / 2) * Real.log ↑N ^ (1 / 2))) Filter.atTop < ⊤SolvedStatement only, no proof