On the calculation of the Dunkl-Williams constant of normed linear spaces

• Autorzy: Hiroyasu Mizuguchi , Kichi-Suke Saito , Ryotaro Tanaka
• Języki publikacji: EN

Abstrakty

EN

Recently, Jiménez-Melado et al. [Jiménez-Melado A., Llorens-Fuster E., Mazcuñán-Navarro E.M., The Dunkl-Williams constant, convexity, smoothness and normal structure, J. Math. Anal. Appl., 2008, 342(1), 298–310] defined the Dunkl-Williams constant DW(X) of a normed linear space X. In this paper we present some characterizations of this constant. As an application, we calculate DW(ℓ2-ℓ∞) in the Day-James space ℓ2-ℓ∞.

Słowa kluczowe

EN

Dunkl-Williams constant; Birkhoff-James orthogonality; norming functional

Kategorie tematyczne

• 46B20: Geometry and structure of normed linear spaces

• Wydawca: De Gruyter Open
• Czasopismo: Open Mathematics
• Rocznik: 2013
• Tom: 11
• Numer: 7
• Strony: 1212-1227

Daty

wydano

2013-07-01

online

2013-04-26

Twórcy

autor

Hiroyasu Mizuguchi

• Department of Mathematical Sciences, Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan

autor

Kichi-Suke Saito

• Department of Mathematics, Faculty of Science, Niigata University, Niigata, 950-2181, Japan

autor

Ryotaro Tanaka

• Department of Mathematical Sciences, Graduate School of Science and Technology, Niigata University, Niigata, 950-2181, Japan

Bibliografia

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Identyfikatory

DOI

10.2478/s11533-013-0238-4