Abstract
It is shown that forL p, 0<p<1, the PeetreK-functional betweenL p andW rp is identically zero. Useful measures that are equivalent to the moduli of smoothness are found. The equivalence results that are given are valid for 0<p≤∞.
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Communicated by Vilmos Totik.
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Ditzian, Z., Hristov, V.H. & Ivanov, K.G. Moduli of smoothness andK-functionals inL p, 0<p<1. Constr. Approx 11, 67–83 (1995). https://doi.org/10.1007/BF01294339
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DOI: https://doi.org/10.1007/BF01294339