数学物理学报(英文版) ›› 2011, Vol. 31 ›› Issue (2): 576-590.

• 论文 • 上一篇    下一篇

ON A CLASS OF KÖTHE SEQUENCE SPACES WITH NORMAL STRUCTURE

B.Zlatanov   

  1. Department of Mathematics and Informatics, Plovdiv University, Bulgaria
  • 收稿日期:2009-03-26 修回日期:2009-09-11 出版日期:2011-03-20 发布日期:2011-03-20
  • 基金资助:

    Research is partially supported by National Fund for Scientific Research of the Bulgarian Ministry of Education and Science, Contract MM-1401/04

ON A CLASS OF KÖTHE SEQUENCE SPACES WITH NORMAL STRUCTURE

B.Zlatanov   

  1. Department of Mathematics and Informatics, Plovdiv University, Bulgaria
  • Received:2009-03-26 Revised:2009-09-11 Online:2011-03-20 Published:2011-03-20
  • Supported by:

    Research is partially supported by National Fund for Scientific Research of the Bulgarian Ministry of Education and Science, Contract MM-1401/04

摘要:

In this note, we investigate the generalized modulus of convexity δ(λ) and the generalized modulus smoothness ρ(λ). We obtain  some estimates of these moduli for X=lp. We obtain inequalities between WCS coefficient of a K\"othe sequence space X and δX(λ). We show that, for a wide class of K\"othe sequence spaces X, if for some ε ∈(0, 9/10] holds δX(ε)>1/3(1-√3/2)ε, then X has normal structure.

关键词: Weakly convergent sequence coefficient, modulus of convexity, generalized modulus of convexity, normal structure

Abstract:

In this note, we investigate the generalized modulus of convexity δ(λ) and the generalized modulus smoothness ρ(λ). We obtain  some estimates of these moduli for X=lp. We obtain inequalities between WCS coefficient of a K\"othe sequence space X and δX(λ). We show that, for a wide class of K\"othe sequence spaces X, if for some ε ∈(0, 9/10] holds δX(ε)>1/3(1-√3/2)ε, then X has normal structure.

Key words: Weakly convergent sequence coefficient, modulus of convexity, generalized modulus of convexity, normal structure

中图分类号: 

  • 46B20