Erdős problem 50
Schoenberg [Sch38] proved that the asymptotic distribution function of exists. That is, for any , the proportion of integers satisfying approaches a limit as . This limit function is the cumulative distribution function of the values of .
Sources
FormalConjectures/ErdosProblems/
50.lean
Retained formal statement
Erdős [Er95] proved that the distribution function of is purely singular: it is continuous, but its derivative is zero almost everywhere.
∀ (f : ℝ → ℝ), Erdos50.IsDistributionOfPhiRatio f → Erdos50.IsPurelySingular fSolvedStatement only, no proof