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Statement

Notation (p. 125): ff is a monic polynomial (1) of degree nn and EE the set where ∣f∣<1|f|<1.

Question (p. 148, in the note added in proof, unnumbered). "Let the restriction that ∣zν∣≤1|z_\nu|\leq1 be removed, and for c>0c>0 let Nn(c)N_n(c) denote the supremum of the number of components of EE whose diameter is greater than 1+c1+c. Is the sequence {Nn(c)}\{N_n(c)\} bounded, for each fixed value of cc?"

It follows the note's answer to Problem 9, which shows that for the threshold 11 (and components of Eˉ\bar E) the count grows at least like n/2n/2. The question counts components of EE, not of Eˉ\bar E.

Source. P. Erdős, F. Herzog, G. Piranian, Metric properties of polynomials, J. Analyse Math. 6 (1958), 125--148, doi:10.1007/BF02790232; the note added in proof on p. 148. The copy read is identified on the source card.

Read depth. Claims checked: the question was read clause by clause on the page image of p. 148 on 2026-10-08. Nothing here is independently reviewed.

Dependencies

Problem 9 and its answer.

Bears on

  • #511: the problem is this question with the threshold written c>1c>1 in place of the paper's 1+c1+c, c>0c>0; both count components of the open set {∣f∣<1}\{|f|<1\} with no restriction on the zeros.