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arXiv · 2509.22210

Mixed modulus of smoothness and best approximation in Lorentz spaces

G. Akishev
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Abstract

The article deals with the mixed modulus of smoothness of positive order and the best approximation by ''angle'' of functions from the Lorentz space $L_{p, \tau}(\mathbb{T}^{m})$. The properties of the mixed modulus of smoothness, the sharp version of the inverse theorem of approximation theory are proved.

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G. Akishev. 2025-09-26. Mixed modulus of smoothness and best approximation in Lorentz spaces. https://arxiv.org/abs/2509.22210

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