On quasi-A(n,k) class operators
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To study the operator inequalities, the notions of class A op-erators and quasi-class A operators are developed up to recently. In thispaper, quasi-A(n, k) class operator for n ≥ 2 and k ≥ 0 is introducedas a new notion, which generalizes the quasi-class A operator. We ob-tain some structural properties of these operators. Also we characterizequasi-A(n, k) classes for n and k via backward extension of weighted shiftoperators. Finally, we give a simple example of quasi-A(n, k) operatorswith two variables.
Abstract
To study the operator inequalities, the notions of class A op-erators and quasi-class A operators are developed up to recently. In thispaper, quasi-A(n, k) class operator for n ≥ 2 and k ≥ 0 is introducedas a new notion, which generalizes the quasi-class A operator. We ob-tain some structural properties of these operators. Also we characterizequasi-A(n, k) classes for n and k via backward extension of weighted shiftoperators. Finally, we give a simple example of quasi-A(n, k) operatorswith two variables.
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