N-B级数的Fejer和的渐近公式(英文)

AN ASYMPTOTIC FORMULA FOR THE FEJER SUMS OF NEUMANN-BESSEL SERIES

设ｆ（ｚ）是单位圆周Г上的有界变差函数，且它的两个单侧导数在点ｚ0∈Г存在，本文给出它的Ｎ－Ｂ级数的Ｆｅｊｅｒ和在ｚ０处的渐近公式．

Let f(z) be of bounded variation on the unite circle F and its two one-side derivatives at zex-exist. Here we give an asymptotic formula at ic for the Fejer sum of Neumann-Bessel series of f(z).