output
20092021
most citedTwo closed forms for the Bernoulli polynomials

77 citations

researchers with a paper here

Counting papers with at most 25 authors, so collaboration author lists do not stand in for the people here.

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Showing 2009 · math.CAShow all

4 papers · 2 filters

math.CA2009★ 21 cited

Necessary and sufficient conditions for a function involving divided differences of the di- and tri-gamma functions to be completely monotonic

Feng Qi, Bai-Ni Guo

In the present paper, necessary and sufficient conditions are established for a function involving divided differences of the digamma and trigamma functions to be completely monoto…

math.CA2009★ 29 cited

Sharp inequalities for polygamma functions

Feng Qi, Bai-Ni Guo

The main aim of this paper is to prove that the double inequality \frac{(k-1)!}{\Bigl\{x+\Bigl[\frac{(k-1)!}{|ψ^{(k)}(1)|}\Bigr]^{1/k}\Bigr\}^k} +\frac{k!}{x^{k+1}}<\bigl|ψ^{(k)}(x…

math.CA2009★ 6 cited

A note on additivity of polygamma functions

Feng Qi, Bai-Ni Guo

In the note, the functions $\abs{ψ^{(i)}(e^x)}$ for are proved to be sub-additive on and super-additive on , where $θ_i\in(0,1)…

math.CA2009★ 55 cited

Bounds for the ratio of two gamma functions--From Wendel's limit to Elezović-Giordano-Pečarić's theorem

Feng Qi

In the survey paper, along one of main lines of bounding the ratio of two gamma functions, we look back and analyse some known results, including Wendel's, Gurland's, Kazarinoff's,…