Weighted Maximum Over Minimum Modulus of Polynomials, Applied to Ray Sequences of Padé Approximants
نویسندگان
چکیده
منابع مشابه
Weighted Maximum over Minimum Modulus of Polynomials, Applied to Ray Sequences of Padé Approximants
Let a 0; " > 0. We use potential theory to obtain a sharp lower bound for the linear Lebesgue measure of the set ( r 2 [0; 1] : r maxjtj=1 jP (t)j minjtj=r jP (t)j " ) : Here P is an arbitrary polynomial of degree n. We then apply this to diagonal and ray Padé sequences for functions analytic (or meromorphic) in the unit ball. For example, we show that the diagonal f[n=n]gn=1 sequence provides ...
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ژورنال
عنوان ژورنال: Constructive Approximation
سال: 2002
ISSN: 0176-4276,1432-0940
DOI: 10.1007/s00365-001-0013-9