Proceedings of the American Mathematical Society

Author(s): V. Kordula; V. Müller
Journal: Proc. Amer. Math. Soc. 124 (1996), 3055-3061.
MSC (1991): Primary 47A10, 47A53
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Abstract: If $T$

is an s-regular operator in a Banach space (i.e. $T$

has closed range and $N(T)\subset R^{\infty }(T)$ ) and $\gamma (T)$ is the Kato reduced minimum modulus, then

$\begin{equation*}\lim _{n\to \infty }\gamma (T^{n})^{1/n}=\sup \{r: T-\lambda { \operatorname {is s-regular for }}|\lambda |<r\}. \end{equation*}$

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Retrieve articles in Proceedings of the American Mathematical Society with MSC (1991): 47A10, 47A53

V. Kordula
Affiliation: Institute of Mathematics AV ČR, Žitná 25, 115 67 Praha 1, Czech Republic

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