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Extensions of the results on powers of -hyponormal and -hyponormal operators

Journal of Inequalities and Applications volume 2006, Article number: 36919 (2006) Cite this article

Abstract

Firstly, we will show the following extension of the results on powers of-hyponormal and-hyponormal operators: let and be positive integers, if is-hyponormal for, then: (i) in case, and hold, (ii) in case, and hold. Secondly, we will show an estimation on powers of-hyponormal operators for which implies the best possibility of our results. Lastly, we will show a parallel estimation on powers of-hyponormal operators as follows: let, then the following hold for each positive integer and: (i) there exists a log-hyponormal operator such that , (ii) there exists a-hyponormal operator such that.

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  1. College of Mathematics and Information Science, Henan Normal University, Xinxiang, 453007, China

    Changsen Yang & Jiangtao Yuan

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  1. Changsen Yang
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  2. Jiangtao Yuan
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Correspondence to Changsen Yang.

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Open Access This article is distributed under the terms of the Creative Commons Attribution 2.0 International License ( https://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Yang, C., Yuan, J. Extensions of the results on powers of -hyponormal and -hyponormal operators. J Inequal Appl 2006, 36919 (2006). https://doi.org/10.1155/JIA/2006/36919

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