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Monotonicity results of ratio between two normalized remainders of Maclaurin series expansion for square of tangent function

  • Xin-Le Liu and Feng Qi EMAIL logo
Published/Copyright: June 9, 2025
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Abstract

In the paper, in view of the monotonicity rule for the ratio between two Maclaurin power series and by virtue of establishment of a monotonicity result for a sequence involving the ratio between two Bernoulli numbers, the authors investigate the monotonicity of the ratio between two normalized remainders of the Maclaurin power series expansion for the square of the tangent function.

2020 Mathematics Subject Classification: Primary 41A80; Secondary 26A48; 26D05; 33B10; 41A58

The second and corresponding author was partially supported by the Youth Project of Hulunbuir City for Basic Research and Applied Basic Research (Grant No. GH2024020).


Acknowledgement

The authors appreciate the anonymous referees for their careful reading, valuable comments, and helpful suggestions to the original version of this paper.

  1. (Communicated by Tomasz Natkaniec)

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Received: 2024-10-06
Accepted: 2025-01-21
Published Online: 2025-06-09
Published in Print: 2025-06-26

© 2025 Mathematical Institute Slovak Academy of Sciences

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