Best approximation in the supremum norm by analytic and harmonic functions. (English) Zbl 1134.41320

Khavinson, Dmitry; Shapiro, Harold S.

Ark. Mat. 39, No. 2, 339-359 (2001).

MSC:

41A30	Approximation by other special function classes
30E10	Approximation in the complex plane
41A50	Best approximation, Chebyshev systems
41A52	Uniqueness of best approximation

References:

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