Extension of Mazhar’s theorem on summability factors



By  (X; Y ) we denote the set of all sequences such thatPa nnis summable  X wheneverPa n is summable Y , where X and Y are sum-mability methods. In this paper we characterize the set  (jC; jk ;N; p n)  fork >  1; > 􀀀1 and arbitrary positive sequence (pn) using functional analytictechniques, and so extend the known results of Mazhar  [2] ; Mehdi [3] and theauthor  [10; 12].


Absolute Cesàro summability; absolute Riesz summability; bounded linear operators; matrix transformations; summability factors.

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