Lower bounds for Jung constants of Orlicz sequence spaces

• Autorzy: Z. D. Ren
• Języki publikacji: EN

Abstrakty

EN

A new lower bound for the Jung constant $JC(l^{(Φ)})$ of the Orlicz sequence space $l^{(Φ)}$ defined by an N-function Φ is found. It is proved that if $l^{(Φ)}$ is reflexive and the function tΦ'(t)/Φ(t) is increasing on $(0,Φ^{-1}(1)]$, then
$JC(l^{(Φ)}) ≥ (Φ^{-1}(1/2))/(Φ^{-1}(1))$.
Examples in Section 3 show that the above estimate is better than in Zhang's paper (2003) in some cases and that the results given in Yan's paper (2004) are not accurate.

• Wydawca: Institute of Mathematics Polish Academy of Sciences
• Czasopismo: Annales Polonici Mathematici
• Rocznik: 2010
• Tom: 97
• Numer: 1
• Strony: 23-34

Daty

wydano

2010

Twórcy

autor

Z. D. Ren

• Department of Mathematics, University of California, Riverside, CA 92521, U.S.A.

Identyfikatory

DOI

10.4064/ap97-1-2