Best constants of harmonic approximation of some convolution classes associated with Laplace operator in d-variables  

作　　者：LING Bo LIU YongPing 

机构地区：[1]School of Mathematical Sciences,Beijing Normal University,Laboratory of Mathematics and Complex Systems,Ministry of Education

出　　处：《Science China Mathematics》2013年第2期301-313,共13页中国科学：数学（英文版）

基　　金：supported partly by National Natural Science Foundation of China(GrantNo.11071019);Research Fund for the Doctoral Program of Higher Education and Beijing Natural Science Foundation(Grant No.1102011)

摘　　要：In this paper,we consider the best EFET(entire functions of the exponential type) approximations of some convolution classes associated with Laplace operator on R d and obtain exact constants in the spaces L1(R2) and L2(Rd).Moreover,the best constants of trigonometric approximations of their analogies on Td are also gained.In this paper, we consider the best EFET （entire functions of the exponential type） approximations of some convolution classes associated with Laplace operator on R^d and obtain exact constants in the spaces L1 （R^2） and L^2（R^d）. Moreover, the best constants of trigonometric approximations of their analogies on T^d are also gained.

关 键 词：best approximation exact constant Laplace operator trigonometric polynomials entire functionsof exponential type 

分 类 号：O177.6[理学—数学]