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Massiveness of the sets of extremal functions in some problems in approximation theory

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It is proved that the sets of extremal functions are massive in some problems in approximation theory.

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Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 10, pp. 1356–1361, October, 1993.

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Kofanov, V.A. Massiveness of the sets of extremal functions in some problems in approximation theory. Ukr Math J 45, 1520–1527 (1993). https://doi.org/10.1007/BF01571086

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