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arXiv · 1709.02846

Density of spaces of trigonometric polynomials with frequencies from a subgroup in $L^\alpha$-spaces

Juan Miguel Medina·Lutz Peter Klotz·Manfred Riedel
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Abstract

Let $G$ be an LCA group, $H$ a closed subgroup, $\varGamma$ the dual group of $G$ and $\mu$ be a regular finite non-negative Borel measure on $\varGamma$. We give some necessary and sufficient conditions for the density of the set of trigonometric polynomials on $\varGamma$ with frequencies from $H$ in the space $L^\alpha(\mu), \alpha \in (0,\infty)$.

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Juan Miguel Medina, Lutz Peter Klotz, Manfred Riedel. 2017-09-08. Density of spaces of trigonometric polynomials with frequencies from a subgroup in $L^\alpha$-spaces. https://arxiv.org/abs/1709.02846

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