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Erdős problem 509

Let f(z)∈C[z]f(z) ∈ ℂ[z] be a monic non-constant polynomial. Can the set {z∈C:∣f(z)∣≤1}\{z ∈ ℂ : |f(z)| ≤ 1\} be covered by a set of closed discs the sum of whose radii is ≤2≤ 2?

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The source's own material, retained exactly.

5 retained statements36c6d0fef71a

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FormalConjectures/ErdosProblems/

509.lean

Retained formal statement1 of 5
FormalConjectures/ErdosProblems/509.leanErdos509.BoundedDiscCover.bound_nonneg_of_nonempty2 linesExact file
∀ {M : Type u} [inst : MetricSpace M] (S : Set M),  S.Nonempty → ∀ (r : ℝ) (ι : Type v) (bdc : Erdos509.BoundedDiscCover S r ι), 0 < r
APIStatement only, no proof