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arXiv · 1305.0575

Weak type (1, 1) inequalities for discrete rough maximal functions

Mariusz Mirek
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Abstract

The aim of this paper is to show that the discrete maximal function $$\mathcal{M}_{h}f(x)=\sup_{N\in\mathbb{N}}\frac{1}{|\mathbf{N}_{h}\cap[1, N]|}\Big|\sum_{n\in \mathbf{N}_{h}\cap[1, N]}f(x-n)\Big|,\ \ \mbox{for $x\in\mathbb{Z}$},$$ is of weak type $(1, 1)$, where $\mathbf{N}_{h}=\{n\in\mathbb{N}: \exists_{m\in\mathbb{N}}\ n=\lfloor h(m)\rfloor\}$ for an appropriate function $h$. As a consequence we also obtain pointwise ergodic theorem along the set $\mathbf{N}_{h}$.

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Mariusz Mirek. 2013-05-02. Weak type (1, 1) inequalities for discrete rough maximal functions. https://arxiv.org/abs/1305.0575

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