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A Global Inverse Theorem for Combinations of Phillips Operators

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Abstract

In the present paper, we prove a global inverse theorem for approximation of bounded continuous functions on the interval [0, ∞) by linear combinations of Phillips operators. Our estimate is in terms of Ditzian–Totik modulus of smoothness and the combinations are in the general form of linear combinations, considered in the book of Ditzian–Totik. Our main theorem extends and generalizes the previous results, obtained by C. P. May, V. Gupta, R. P. Agrawal, etc.

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  1. Department of Mathematics, University of Architecture, Civil Engineering and Geodesy, BG-1046, Sofia, Bulgaria

    Gancho Tachev

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  1. Gancho Tachev
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Tachev, G. A Global Inverse Theorem for Combinations of Phillips Operators. Mediterr. J. Math. 13, 2709–2719 (2016). https://doi.org/10.1007/s00009-015-0648-6

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  • DOI: https://doi.org/10.1007/s00009-015-0648-6

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