$\alpha$-monotone sequences and the Lorentz theorem
Vestnik Moskovskogo universiteta. Matematika, mehanika, no. 2 (2023), pp. 63-67
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Properties of $\alpha$-monotone sequences are studied. A relationship between $\alpha$-monotonicity and the limiting rate of change of coefficients is revealed. Operations on sequences that do not lead out of the class $M_\alpha$ are discussed. An analogue of the Lorentz theorem for trigonometric series with coefficients from the classes $M_\alpha$ for $0 <\alpha <1$ is proved.
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