摘 要: | The author gives some disagreement to the following result,which is published in [1].Let {L_n(f(}be mass-concerntative,φ_n→0+(n→∞),0<α≤2 andC~(-1)≤(φn+1)/(φn)≤C(n=1,2,…)for some constrant C>0.Then for any f∈C[-2a,2a],||L_n(f)-f||σ[-a,a]=O(φ_n~α)implies f∈Lip*α,whereLip*a={f∈C[-2a,2a]|w_2(f,δ)[-2a,2a]=O(δ~α)}.Then some similar results on C_(2π)are given,and further some results on C[-2a,2a]areestablished by adding some proper conditions.
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