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arXiv · 1211.5424

Approximation of continuous periodic functions by de la Vallee Poussin sums

Ie. Yu. Ovsii·A. S. Serdyuk
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Abstract

We obtain an estimate of the deviation of de la Vallee Poussin sums V_{n,n/2}(f;x) from continuous functions f, expressed in terms of values of theirs modulus of continuity. It is established that this estimate can't be improved by using the well-known analogue of the Lebesgue inequality for de la Vallee Poussin sums

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Ie. Yu. Ovsii, A. S. Serdyuk. 2012-11-23. Approximation of continuous periodic functions by de la Vallee Poussin sums. https://arxiv.org/abs/1211.5424

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