On discrete norms of polynomials
نویسندگان
چکیده
For a polynomial p of degree n<N we compare two norms: ‖p‖ := sup{|p(z)| : z ∈ C; |z| = 1} and ‖p‖N := sup {∣∣p (zj )∣∣ : j = 0, . . . , N − 1} ; zj = e2 i j N . We show that there exist universal constants C1 and C2 such that 1+ C1 log ( N N − n ) sup { ‖p‖ ‖p‖N : p ∈ Pn } C2 log ( N N − n ) + 1. © 2005 Elsevier Inc. All rights reserved.
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ورودعنوان ژورنال:
- Journal of Approximation Theory
دوره 139 شماره
صفحات -
تاریخ انتشار 2006