𝑘-hyponormality of powers of weighted shifts via Schur products

Curto, Raúl; Park, Sang

doi:10.1090/S0002-9939-02-06805-3

$k$-hyponormality of powers of weighted shifts via Schur products
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Proc. Amer. Math. Soc. 131 (2003), 2761-2769 Request permission

Abstract:

We characterize $k$-hyponormality and quadratic hyponormality of powers of weighted shifts using Schur product techniques.

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