A Sharp Estimate for the Hardy-littlewood Maximal Function
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چکیده
The best constant in the usual L norm inequality for the centered Hardy-Littlewood maximal function on R is obtained for the class of all “peak-shaped” functions. A function on the line is called “peakshaped” if it is positive and convex except at one point. The techniques we use include variational methods. AMS Classification (1991): 42B25 0. Introduction. Let (0.1) (Mf)(x) = sup δ>0 1 2δ ∫ x+δ
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تاریخ انتشار 1997