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Some inequalities of Hardy-Littlewood type. (English) Zbl 0816.42017
G. H. Hardy and J. E. Littlewood [J. Reine Angew. Math. 157, 141-158 (1927; JFM 53.0193.03)] proved some very important inequalities having particular significance in applications. Several theorems concerning convergence and summability of orthogonal series apply these well-known inequalities. In this paper some related results for quasi-monotonic sequences are given.

##### MSC:
 42C15 General harmonic expansions, frames 26D15 Inequalities for sums, series and integrals
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##### References:
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