Unbounded generalized B-Fredholm operators
DOI:
https://doi.org/10.17398/Keywords:
Unbounded generalized B-Fredholm operators, operator of Saphar type, generalized B-Fredholm spectrum, quasi-Fredholm operatorAbstract
In this paper, we investigate a new class of unbounded linear operators, that is, the unbounded generalized B-Fredholm operators in Banach space. More explicitly, we provide a characterization of this class of operators and some of its basic properties on a Banach space. Moreover, we study the generalized B-Fredholm spectrum and we prove a perturbation result of an unbounded generalized B-Fredholm operator under a commuting power finite-rank operator.
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