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Regularity properties of the element of closest approximation. (English) Zbl 0273.43005


MSC:

43A15 \(L^p\)-spaces and other function spaces on groups, semigroups, etc.
41A50 Best approximation, Chebyshev systems
42A45 Multipliers in one variable harmonic analysis
Full Text: DOI

References:

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[14] -, Fourier multipliers whose multiplier norm is an attained value, Proc. Sympos. Linear Operators and Approximation (Oberwolfach, Germany, Aug. 1971) (to appear).
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