erdos_509.variants.Pommerenke_bound

Let $f(z) ∈ $ℂ[z]$ be a monic non-constant polynomial. Can the set $\{z ∈ ℂ : |f(z)| ≤ 1\}$ be covered by a set of closed discs the sum of whose radii is $≤ 2.59$? Solution: True. This is due to Pommerenke.

theorem erdos_509.variants.Pommerenke_bound : answer(True) ↔ ∀ (f : ℂ[X]), f.Monic → f.natDegree ≠ 0 →
    ∃ (ι : Type), Nonempty (BoundedDiscCover {z | ‖f.eval z‖ ≤ 1} 2.59 ι)

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