On the Flatness of Semi-Cubically Hyponormal Weighted Shifts
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Let W_{\alpha } be a weighted shift with positive weight sequence $\alpha =\{\alpha _{i}\}_{i=0}^{\infty }. The semi-cubical hyponormality of W_{\alpha } is introduced and some flatness properties of W_{\alpha } are discussed in this note. In particular, In particular, it is proved that if $\alpha _{n}=\alpha_{n+1}$ for some $n\geq 1,$ then $\alpha_{n+k}=\alpha_{n}$ for all $k \ge 1$.
Abstract
Let W_{\alpha } be a weighted shift with positive weight sequence $\alpha =\{\alpha _{i}\}_{i=0}^{\infty }. The semi-cubical hyponormality of W_{\alpha } is introduced and some flatness properties of W_{\alpha } are discussed in this note. In particular, In particular, it is proved that if $\alpha _{n}=\alpha_{n+1}$ for some $n\geq 1,$ then $\alpha_{n+k}=\alpha_{n}$ for all $k \ge 1$.
참고문헌 (12)
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