• Corpus ID: 233289484

Zeros of optimal polynomial approximants in $\ell^p_{A}$

@inproceedings{Cheng2021ZerosOO,
title={Zeros of optimal polynomial approximants in \$\ell^p\_\{A\}\$},
author={Raymond Cheng and William T. Ross and Daniel Seco},
year={2021}
}
• Published 16 April 2021
• Mathematics
The study of inner and cyclic functions in lpA spaces requires a better understanding of the zeros of the so-called optimal polynomial approximants. We determine that a point of the complex plane is the zero of an optimal polynomial approximant for some element of lpA if and only if it lies outside of a closed disk (centered at the origin) of a particular radius which depends on the value of p. We find the value of this radius for p 6= 2. In addition, for each positive integer d there is a…

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