Approximation by semi-Fredholm operators

Galaz-Fontes, Fernando

doi:10.1090/S0002-9939-1994-1197536-2

Approximation by semi-Fredholm operators
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by Fernando Galaz-Fontes

Proc. Amer. Math. Soc. 120 (1994), 1219-1222

DOI: https://doi.org/10.1090/S0002-9939-1994-1197536-2

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Abstract:

We present a simple approach for calculating some known distances from a bounded operator defined on a separable Hilbert space to certain sets related to semi-Fredholm operators.

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