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arXiv · 1710.02060

On the best Hardy constant for quasi-arithmetic means and homogeneous deviation means

Zsolt Páles·Paweł Pasteczka
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Abstract

The aim of this paper is to characterize the so-called Hardy means, i.e., those means $M\colon\bigcup_{n=1}^\infty \mathbb{R}_+^n\to\mathbb{R}_+$ that satisfy the inequality $$ \sum_{n=1}^\infty M(x_1,\dots,x_n) \le C\sum_{n=1}^\infty x_n $$ for all positive sequences $(x_n)$ with some finite positive constant $C$. The smallest constant $C$ satisfying this property is called the Hardy constant of the mean $M$. In this paper we determine the Hardy constant in the cases when the mean $M$ is either a concave quasi-arithmetic or a concave and homogeneous deviation mean.

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BibTeXRIS

Zsolt Páles, Paweł Pasteczka. 2018-02-18. On the best Hardy constant for quasi-arithmetic means and homogeneous deviation means. https://doi.org/10.7153/mia-2018-21-43

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