Best mean square approximations by entire functions of finite degree on a straight line and exact values of mean widths of functional classes

被引：0

作者：

S. B. Vakarchuk

V. G. Doronin

机构：

[1] Dnepropetrovsk University of Economics and Law,

[2] Gonchar Dnepropetrovsk National University,undefined

来源：

Ukrainian Mathematical Journal | 2011年 / 62卷

关键词：

Entire Function; Functional Classis; Nonnegative Function; Cubature Formula; Arbitrary Positive Number;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

We obtain exact Jackson-type inequalities in the case of the best mean square approximation by entire functions of finite degree ≤ σ on a straight line. For classes of functions defined via majorants of averaged smoothness characteristics Ω1(f, t ), t > 0, we determine the exact values of the Kolmogorov mean ν-width, linear mean ν-width, and Bernstein mean ν-width, ν > 0.

引用

页码：1199 / 1212

页数：13

共 20 条

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