Lower bounds for widths of classes of convolutions of periodic functions in the metrics of $C$ and $L$

• Date: 1995
• Main Authors: Serdyuk, A. S., Stepanets, O. I., Сердюк, А. С., Степанец, А. И.
• Format: Article
• Language: Russian
• Published: Institute of Mathematics, NAS of Ukraine 1995
• Online Access: https://umj.imath.kiev.ua/index.php/umj/article/view/5507
• Journal Title: Ukrains’kyi Matematychnyi Zhurnal

We give new sufficient conditions for kernels to belong to the set $C_{y, 2n}$ introduced by Kushpel'. These conditions give the possibility of extending the set of kernels belonging to $C_{y, 2n}$. On the basis of these results, we obtain lower bounds for the Kolmogorov widths of classes o...