Author(s): Shi Xianliang
Pages: 1-6
Year: 1981 Issue:  S1
Journal: Journal of Mathematical Research and Exposition
Keyword:  可和性; Fourier级数; 子列; 求和矩阵; 引理; 自然数; Riemann; 求和法; 卷积算子; 子序列;
Abstract: Let Hα0 denote the set of functions such that being a given modulus of continuity. Let {nk} be a set of natural numbers satisfying the condition , and let A= (απk) be a regular summation matrix. Assume that with Dn(x) denoting the Dirichlet kernel. In this paper it is proved that the necessary and sufficient condition for to be valid for all is given by (4).