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arXiv · 2001.02130

Polynomial approach to cyclicity for weighted $\ell^p_A$

Abstract

In previous works, an approach to the study of cyclic functions in reproducing kernel Hilbert spaces has been presented, based on the study of so called \emph{optimal polynomial approximants}. In the present article, we extend such approach to the (non-Hilbert) case of spaces of analytic functions whose Taylor coefficients are in $\ell^p(\omega)$, for some weight $\omega$. When $\omega=\{(k+1)^\alpha\}_{k\in \mathbb{N}}$, for a fixed $\alpha \in \mathbb{R}$, we derive a characterization of the cyclicity of polynomial functions and, when $1<p<\infty$, we obtain sharp rates of convergence of the optimal norms.

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BibTeXRIS

Daniel Seco, Roberto Téllez. 2020-01-07. Polynomial approach to cyclicity for weighted $\ell^p_A$. https://arxiv.org/abs/2001.02130

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