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A pythagorean approach in Banach spaces

Abstract

Let be a Banach space and let be the unit sphere of. Parameters,,, and, where and are introduced and studied. The values of these parameters in the spaces and function spaces are estimated. Among the other results, we proved that a Banach space with, or is uniform nonsquare; and a Banach space with, or has uniform normal structure.

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Correspondence to Ji Gao.

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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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Gao, J. A pythagorean approach in Banach spaces. J Inequal Appl 2006, 94982 (2006). https://doi.org/10.1155/JIA/2006/94982

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  • DOI: https://doi.org/10.1155/JIA/2006/94982

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