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http://dx.doi.org/10.4134/CKMS.c180110

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)
Publication Information
Communications of the Korean Mathematical Society / v.34, no.2, 2019 , pp. 477-486 More about this Journal
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].
Keywords
weighted shifts; hyponormality; semi-cubic hyponormality;
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Times Cited By KSCI : 2  (Citation Analysis)
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