Erdős problem 67
The Erdős discrepancy problem
Sources
FormalConjectures/ErdosProblems/
67.lean
Retained formal statement
The Erdős discrepancy problem (complex variant)
If then is it true that for every there exist such that This is true, and was proved by Tao [Ta16]
∀ (f : ℕ → ↑(Metric.sphere 0 1)) (C : ℝ), 0 < C → ∃ d ≥ 1, ∃ m ≥ 1, C < ‖∑ k ∈ Finset.Icc 1 m, ↑(f (k * d))‖SolvedStatement only, no proof