Guo, Bai-Ni; Qi, Feng Refinements of lower bounds for polygamma functions. (English) Zbl 1267.33003 Proc. Am. Math. Soc. 141, No. 3, 1007-1015 (2013). Reviewer: József Sándor (Cluj-Napoca) MSC: 33B15 26D07 PDFBibTeX XMLCite \textit{B.-N. Guo} and \textit{F. Qi}, Proc. Am. Math. Soc. 141, No. 3, 1007--1015 (2013; Zbl 1267.33003) Full Text: DOI arXiv
Chen, Chao-Ping; Qi, Feng The best bounds in Wallis’ inequality. (English) Zbl 1049.05006 Proc. Am. Math. Soc. 133, No. 2, 397-401 (2005). MSC: 05A20 05A10 26D20 33B15 PDFBibTeX XMLCite \textit{C.-P. Chen} and \textit{F. Qi}, Proc. Am. Math. Soc. 133, No. 2, 397--401 (2005; Zbl 1049.05006) Full Text: DOI
Qi, Feng Logarithmic convexity of extended mean values. (English) Zbl 0993.26012 Proc. Am. Math. Soc. 130, No. 6, 1787-1796 (2002). Reviewer: I.Raşa (Cluj-Napoca) MSC: 26D15 26A51 26E60 26B25 PDFBibTeX XMLCite \textit{F. Qi}, Proc. Am. Math. Soc. 130, No. 6, 1787--1796 (2002; Zbl 0993.26012) Full Text: DOI
Qi, Feng; Xu, Sen-Lin The function \((b^{x}-a^{x})/x\): Inequalities and properties. (English) Zbl 0904.26006 Proc. Am. Math. Soc. 126, No. 11, 3355-3359 (1998). Reviewer: I.Raşa (Cluj-Napoca) MSC: 26A48 26D07 26D15 PDFBibTeX XMLCite \textit{F. Qi} and \textit{S.-L. Xu}, Proc. Am. Math. Soc. 126, No. 11, 3355--3359 (1998; Zbl 0904.26006) Full Text: DOI