The Ptolemy constant of absolute normalized norms on ℝ2
Department of Mathematics and Statistics, Chongqing Three Gorges University, Wanzhou 404000, China
Journal of Inequalities and Applications 2012, 2012:107 doi:10.1186/1029-242X-2012-107Published: 17 May 2012
We determine and estimate the Ptolemy constant of absolute normalized norms on ℝ2 by means of their corresponding continuous convex functions on [0, 1]. Moreover, the exact values were calculated in some concrete Banach spaces.
2000 Mathematics Subject Classification: 46B20.