U. Goginava

Cesaro Means of Trigonometric Fourier Series

L. Zhizhiashvili proved that if f belongs to Hpw for some p, 1 <= p <= infinity, and 0 < a < 1, then the Lp-deviation of f from its Cesaro mean is O(naw(1/n)) where w(.) is a modulus of continuity. We show that this estimation is non-amplifiable for p = 1.