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arXiv · 2011.03362

Linear polynomial approximation schemes in Banach holomorphic function spaces

Javad Mashreghi·Thomas Ransford
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Abstract

Let $X$ be a Banach holomorphic function space on the unit disk. A linear polynomial approximation scheme for $X$ is a sequence of bounded linear operators $T_n:X\to X$ with the property that, for each $f\in X$, the functions $T_n(f)$ are polynomials converging to $f$ in the norm of the space. We completely characterize those spaces $X$ that admit a linear polynomial approximation scheme. In particular, we show that it is NOT sufficient merely that polynomials be dense in $X$.

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Javad Mashreghi, Thomas Ransford. 2020-11-04. Linear polynomial approximation schemes in Banach holomorphic function spaces. https://doi.org/10.1007/s13324-019-00312-y

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