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arXiv · 1602.01408

Supraposinormality and hyponormality for the generalized Ces\`aro matrices of order two

H. C. Rhaly Jr
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Abstract

It is well known that the generalized Ces\`aro matrices of order one are hyponormal operators on $\ell^2$, and it has recently been shown that the Ces\`aro matrix of order two is also hyponormal. Here the relatively new concept of supraposinormality is used to show that the generalized Ces\`aro matrices of order two are both posinormal and coposinormal, and that "most" of them are also hyponormal. A conjecture is propounded that would extend the hyponormality result.

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H. C. Rhaly Jr. 2016-02-03. Supraposinormality and hyponormality for the generalized Ces\`aro matrices of order two. https://arxiv.org/abs/1602.01408

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