Refinements of lower bounds for polygamma functions

Guo, Bai-Ni; Qi, Feng

doi:10.1090/S0002-9939-2012-11387-5

Refinements of lower bounds for polygamma functions
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by Bai-Ni Guo and Feng Qi PDF

Proc. Amer. Math. Soc. 141 (2013), 1007-1015 Request permission

Abstract:

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

References

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