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Refinements of lower bounds for polygamma functions


Authors: Bai-Ni Guo and Feng Qi
Journal: Proc. Amer. Math. Soc. 141 (2013), 1007-1015
MSC (2010): Primary 33B15; Secondary 26D07
DOI: https://doi.org/10.1090/S0002-9939-2012-11387-5
Published electronically: August 9, 2012
MathSciNet review: 3003692
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Abstract | References | Similar Articles | Additional Information

Abstract: In the paper, some lower bounds for polygamma functions are refined. Moreover, several open problems are posed.


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Additional Information

Bai-Ni Guo
Affiliation: School of Mathematics and Informatics, Henan Polytechnic University, Jiaozuo City, Henan Province, 454010, People’s Republic of China
Email: bai.ni.guo@gmail.com

Feng Qi
Affiliation: School of Mathematics and Informatics, Henan Polytechnic University, Jiaozuo City, Henan Province, 454010, People’s Republic of China
Email: qifeng618@gmail.com

DOI: https://doi.org/10.1090/S0002-9939-2012-11387-5
Keywords: Refinement, lower bound, polygamma function, inequality, mean, open problem
Received by editor(s): December 13, 2009
Received by editor(s) in revised form: March 2, 2011, and August 4, 2011
Published electronically: August 9, 2012
Additional Notes: The second author was partially supported by the China Scholarship Council and the Science Foundation of Tianjin Polytechnic University
Communicated by: Walter Van Assche
Article copyright: © Copyright 2012 American Mathematical Society
The copyright for this article reverts to public domain 28 years after publication.

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