Chebyshev constants for the unit circle
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چکیده
It is proven that for any system of n points z1, . . . , zn on the (complex) unit circle, there exists another point z of norm 1, such that ∑ 1 |zk − z|2 6 n 4 . Two proofs are presented: one uses a characterisation of equioscillating rational functions, while the other is based on Bernstein’s inequality.
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تاریخ انتشار 2011