Strong converse results for Bernstein - Durrmeyer operators and their quasi - interpolants
نویسندگان
چکیده
The purpose of this paper is the investigation of strong converse results for Bernstein-Durrmeyer operators and their quasi-interpolants. For lower dimensions we improve known results by Knoop and Zhou [16] and Chen, Ditzian and Ivanov [5] in regard to the constants in their estimates and prove a strong converse theorem of type B for the quasi-interpolants introduced by Berdysheva, Jetter and Stöckler (see e. g. [2]) with respect to a modified K-functional in the univariate case. 2000 Mathematics Subject Classification: 41A10, 41A17, 41A27, 41A36, 41A44
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