Abstract
Necessary and sufficient conditions on a compact set X in ℂ and a self-homeomorphism ψ of the plane ℂ are studied under which any function continuous on X can be approximated uniformly on X by functions of the form p + h ∘ ψ, where p is a polynomial in a complex variable and h is a rational function whose poles belong to the bounded components of the complement to the compact set ψ(X).
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Original Russian Text © A. B. Zaitsev, 2011, published in Matematicheskie Zametki, 2011, Vol. 89, No. 1, pp. 34–42.
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Zaitsev, A.B. On the closure of the sum of two uniform algebras on compact sets in ℂ. Math Notes 89, 51–58 (2011). https://doi.org/10.1134/S0001434611010056
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DOI: https://doi.org/10.1134/S0001434611010056