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Approximation by Boolean sums of linear operators: Telyakovskiǐ-type estimates

Published online by Cambridge University Press:  17 April 2009

Jia-Ding Cao  and
Heinz H. Gonska
Jia-Ding Cao
Affiliation:
Department of Mathematics Fudan, University Shanghai Peoples, Republic of China
Heinz H. Gonska
Affiliation:
Department of Computer, Science European Business School, D-6227 Oestrich-Winkel, West Germany
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Abstract

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In the present note we study the question: “Under which general conditions do certain Boolean sums of linear operators satisfy Telyakovskiǐ-type estimates?” It is shown, in particular, that any sequence of linear algebraic polynomial operators satisfying a Timan-type inequality can be modified appropriately so as to obtain the corresponding upper bound of the Telyakovskiǐ-type. Several examples are included.

Type
Research Article
Information
Bulletin of the Australian Mathematical Society , Volume 42 , Issue 2 , October 1990 , pp. 253 - 266
Copyright
Copyright © Australian Mathematical Society 1990

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