Final published version
Licence: CC BY: Creative Commons Attribution 4.0 International License
Research output: Contribution to Journal/Magazine › Journal article › peer-review
<mark>Journal publication date</mark> | 31/12/2021 |
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<mark>Journal</mark> | Constructive Approximation |
Issue number | 3 |
Volume | 54 |
Number of pages | 26 |
Pages (from-to) | 529-554 |
Publication Status | Published |
Early online date | 8/11/21 |
<mark>Original language</mark> | English |
The standard well-known Remez inequality gives an upper estimate of the values of polynomials on [- 1 , 1] if they are bounded by 1 on a subset of [- 1 , 1] of fixed Lebesgue measure. The extremal solution is given by the rescaled Chebyshev polynomials for one interval. Andrievskii asked about the maximal value of polynomials at a fixed point, if they are again bounded by 1 on a set of fixed size. We show that the extremal polynomials are either Chebyshev (one interval) or Akhiezer polynomials (two intervals) and prove Totik–Widom bounds for the extremal value, thereby providing a complete asymptotic solution to the Andrievskii problem.