Annals of Functional Analysis

Some geometric constants of absolute normalized norms on $\Bbb R^2$

Hiroyasu Mizuguchi and Kichi-Suke Saito

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We consider the Banach space $X=(\Bbb R^2‎, ‎\|\cdot\|)$ with a normalized‎, ‎absolute norm‎. ‎Our aim in this paper is to calculate the modified Neumann-Jordan constant $C'_{NJ}(X)$ and the Zbăganu constant $C_Z(X)$‎.

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Ann. Funct. Anal., Volume 2, Number 2 (2011), 22- 33.

First available in Project Euclid: 12 May 2014

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Zentralblatt MATH identifier

Primary: 46B20: Geometry and structure of normed linear spaces
Secondary: 46B25: Classical Banach spaces in the general theory

Zbăganu constant ‎absolute norm ‎von ‎‎Neumann-Jordan constant


Mizuguchi, Hiroyasu; Saito, Kichi-Suke. Some geometric constants of absolute normalized norms on $\Bbb R^2$. Ann. Funct. Anal. 2 (2011), no. 2, 22-- 33. doi:10.15352/afa/1399900191.

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