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Open Access Research Article

A pythagorean approach in Banach spaces

Ji Gao

Author Affiliations

Department of Mathematics, Community College of Philadelphia, Philadelphia, PA 19130-3991, USA

Journal of Inequalities and Applications 2006, 2006:94982  doi:10.1155/JIA/2006/94982

The electronic version of this article is the complete one and can be found online at: http://www.journalofinequalitiesandapplications.com/content/2006/1/94982


Received:30 December 2003
Accepted:4 May 2004
Published:3 January 2006

© 2006 Gao

This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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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