Abstract
Best trigonometric approximation in L p , 1≦p≦∞, is characterized by a modulus of smoothness, which is equivalent to zero if the function is a trigonometric polynomial of a given degree. The characterization is similar to the one given by the classical modulus of smoothness. The modulus possesses properties similar to those of the classical one.
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The research was supported by grant No. 49/2009 of the National Science Fund to the University of Sofia.
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Draganov, B.R., Parvanov, P.E. On estimating the rate of best trigonometric approximation by a modulus of smoothness. Acta Math Hung 131, 360–379 (2011). https://doi.org/10.1007/s10474-011-0072-8
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DOI: https://doi.org/10.1007/s10474-011-0072-8