K-functionals and exact values of n-widths for several classes from L2

被引：10

作者：

Vakarchuk, SB ^{[1
]}

机构：

[1] Natl Acad Sci Ukraine, Inst Geotechnol Mech, Kiev, Ukraine

来源：

MATHEMATICAL NOTES | 1999年 / 66卷 / 3-4期

关键词：

function space; Sobolev space; measurable 2 pi-periodic function; function class; K-functional; Kolmogorov; Gelfand; linear; and projection n-width; Fourier series;

D O I：

10.1007/BF02679087

中图分类号：

O1 [数学];

学科分类号：

0701 ; 070101 ;

摘要：

We obtain exact values of different n-widths for certain classes of 2 pi-periodic functions for which the K-functionals of their rth-order derivatives are majorized by functions satisfying specified restrictions. We also consider some examples of majorants satisfying all the restrictions: imposed in the present paper.

引用

页码：404 / 408

页数：5