Interpolation mixed with \(l_ 2\)-approximation
Some relations between interpolation in \(n\)-th roots of unity by rational functions and \(l_2\)-approximation are investigated. The author treats a variant of a minimization problem of \textit{A. Sharma} and \textit{Z. Ziegler} [Stud. Math. 77, 523-528 (1984; Zbl 0567.41020)] and he extends an own result [Bull. Austral. Math. Soc. 37, No. 3, 415-442 (1988; Zbl 0633.30033)].
scientific article; zbMATH DE number 827936