Journal of applied mathematics & informatics

The Korean Society for Computational and Applied Mathematics (한국전산응용수학회)
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NEW RESULTS ON k-HYPONORMALITY OF BACKWARD EXTENSIONS OF SUBNORMAL WEIGHTED SHIFTS

  • DONG, YANWU (Department of Mathematics, Zhanjiang Preschool Education College (Fundamental Education College of Lingnan Normal University)) ;
  • LEE, MI RYEONG (Institute of Liberal Education, Catholic University of Daegu) ;
  • LI, CHUNJI (Department of Mathematics, Northeastern University)
  • Received : 2018.07.19
  • Accepted : 2018.11.05
  • Published : 2019.01.30
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Abstract

In this article, we introduce a new kind of subnormal weighted shifts, which is a generalized form of Bergman shift, and discuss the k-hyponormality of its backward extensions.

Keywords

E1MCA9_2019_v37n1_2_73_f0001.png 이미지

FIGURE 3.1: The regions of k-hyponormality for k = 2, 3, 4 and subnormality.

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