De Branges’ theorem on approximation problems of Bernstein type
نویسندگان
چکیده
منابع مشابه
De Branges’ Theorem on Approximation Problems of Bernstein Type
The Bernstein approximation problem is to determine whether or not the space of all polynomials is dense in a given weighted C0-space on the real line. A theorem of de Branges characterizes non-density by existence of an entire function of Krein class being related with the weight in a certain way. An analogous result holds true for weighted sup-norm approximation by entire functions of exponen...
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Recently, Todorov and Wilf independently realized that de Branges' original proof of the Bieberbach and Milin conjectures and the proof that was later given by Weinstein deal with the same special function system that de Branges had introduced in his work. In this article, we present an elementary proof of this statement based on the deen-ing diierential equations system rather than the closed ...
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ژورنال
عنوان ژورنال: Journal of the Institute of Mathematics of Jussieu
سال: 2013
ISSN: 1474-7480,1475-3030
DOI: 10.1017/s1474748013000030