Abstract
The paper deals with sequences of positive numbers (dn) such that, multiplying the Fourier coefficients (Cn(f)) of functions from given function classes by these numbers, one obtains a convergent series of the form \(\sum {{\rm{|}}{C_n}(f){{\rm{|}}^p}{d_n}, 1 \le p < 2} \). It is established that the resulting conditions cannot be strengthened in a certain sense. The results of the paper imply, in particular, some well-known results for trigonometric Fourier series.
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Tsagareishvili, V.S., Tutberidze, G. Multipliers of Absolute Convergence. Math Notes 105, 439–448 (2019). https://doi.org/10.1134/S0001434619030143
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DOI: https://doi.org/10.1134/S0001434619030143