Wiki
Wiki

Research notes on every problem, and a library of the papers behind them. Built from the open erdos repository.

Updated


Statement

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

Problem 6 (p. 139). "Suppose that FF is a closed set of transfinite diameter 1, and that FF is not contained in any closed disk of radius 1. Can the number of components of EE (all zν∈Fz_\nu\in F) be nn? If the transfinite diameter of FF is less than 1, does there exist a positive constant cc (depending on FF, or perhaps only on the transfinite diameter of FF) such that EE has at most (1−c)n(1-c)n components, when nn is large?"

Source. P. Erdős, F. Herzog, G. Piranian, Metric properties of polynomials, J. Analyse Math. 6 (1958), 125--148, doi:10.1007/BF02790232; Problem 6 on p. 139. The copy read is identified on the source card.

Read depth. Claims checked: the problem was read clause by clause on the page image of p. 139 on 2026-10-08. Nothing here is independently reviewed.

Dependencies

Section 5's discussion (p. 136): for zeros in the closed unit disk EE can have nn components (zn+1z^n+1), and Theorem 7 on the components of Eˉ\bar E.

Bears on

  • #1042: the problem's two questions are those of Problem 6; the paper's second question carries the qualifier "when nn is large", which the problem's statement omits; the problem page's Formulation note reads the question with it.