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arXiv · 1803.03349

Semi-cubically hyponormal weighted shifts with Stampfi's subnormal completion

Seunghwan Baek·Mi Ryeong Lee
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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 $\mathcal{U}:\mathcal{=}\{(x,y):W_{\alpha }$ is semi-cubically hyponormal$\}$ and describe the shape of the boundary of $\mathcal{U}$. In particular, we improve the results of \cite[Theorem 4.2]{LLB} with properties of $\mathcal{U}$.

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Seunghwan Baek, Mi Ryeong Lee. 2018-03-09. Semi-cubically hyponormal weighted shifts with Stampfi's subnormal completion. https://arxiv.org/abs/1803.03349

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