A characterization of some weighted norm inequalities for the fractional maximal function

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Title

Authors ¹

Department of Mathematics, Rutgers University, New Brunswick, New Jersey 08903-2101, U.S.A.

A new characterization is given for the pairs of weight functions v, w for which the fractional maximal function is a bounded operator from

L_{v}^{p} (X)

to

L_{w}^{q} (X)

when 1 < p < q < ∞ and X is a homogeneous space with a group structure. The case when X is n-dimensional Euclidean space is included.

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