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SEMI-CUBICALLY HYPONORMAL WEIGHTED SHIFTS WITH STAMPFLI'S SUBNORMAL COMPLETION

  • Baek, Seunghwan (Department of Mathematics Kyungpook National University) ;
  • Lee, Mi Ryeong (Institute of Liberal Education Daegu Catholic University)
  • Received : 2018.03.19
  • Accepted : 2018.07.19
  • Published : 2019.04.30
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Abstract

Let ${\alpha}:1,(1,{\sqrt{x}},{\sqrt{y}})^{\wedge}$ be a weight sequence with Stampfli's subnormal completion and let $W_{\alpha}$ be its associated weighted shift. In this paper we discuss some properties of the region ${\mathcal{U}}:=\{(x,y):W_{\alpha}$ is semi-cubically hyponormal} and describe the shape of the boundary of ${\mathcal{U}}$. In particular, we improve the results of [19, Theorem 4.2].

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References

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