Abstract
In the Banach space of functions analytic in a Jordan domain \(\Omega \subset \mathbb{C}\), we establish order estimates for the Kolmogorov widths of certain classes of functions that can be represented in Ω by Cauchy-type integrals along the rectifiable curve Γ = ∂Ω and can be analytically continued to Ω′ ⊃ Ω or to \(\mathbb{C}\).
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Romanyuk, V.S. Estimates of the Kolmogorov Widths of Classes of Analytic Functions Representable by Cauchy-Type Integrals. I. Ukrainian Mathematical Journal 53, 259–269 (2001). https://doi.org/10.1023/A:1010417020575
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DOI: https://doi.org/10.1023/A:1010417020575