Approximation spaces, greedy classes and Lorentz spaces

2024/11/20 by Berasategui, Miguel, Berná, Pablo M., García, Andrea
#46B15 #FOS: Mathematics #Functional Analysis (math.FA)

paper · doi:10.48550/arxiv.2411.13678

Abstract

We characterize the approximation spaces of a broad class of bases - which includes almost greedy bases - in terms of weighted Lorentz spaces. For those bases, we also find necessary and sufficient conditions under which the approximation spaces and greedy classes are the same.

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