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Statement

Notation (p. 125): EE is the set where ∣f∣<1|f|<1 and DrD_r the open disk ∣z∣<r|z|<r.

Problem 7 (p. 142). "If all the zeros of ff lie in DrD_r (r<2)(r<2), does the set EE have a component with diameter greater than 2−r2-r?"

Source. P. Erdős, F. Herzog, G. Piranian, Metric properties of polynomials, J. Analyse Math. 6 (1958), 125--148, doi:10.1007/BF02790232; Problem 7 on p. 142. The copy read is identified on the source card.

Read depth. Claims checked: the problem was read on the page image of p. 142 on 2026-10-08; the disk is printed without the bar the paper uses for closed disks. Nothing here is independently reviewed.

Dependencies

None.

Bears on

  • #1048: the problem is Problem 7 with the zeros in the closed disk ∣z∣≤r|z|\le r, where the paper's DrD_r is the open disk ∣z∣<r|z|<r.