Logarithmic convexity of Gini means
In the paper, the monotonicity and logarithmic convexity of Gini means and related functions are investigated.
arXiv subjects
Publications and source records attributed to Bai-Ni Guo.
In the paper, the monotonicity and logarithmic convexity of Gini means and related functions are investigated.
In the present note, an alternative proof is supplied for Theorem~1 in [N. Elezović, C. Giordano and J. Pečarić, \textit{The best bounds in Gautschi's inequality}, Math. Inequal. Appl. \textbf{3} (2000), 239\nobreakdash--252.].
In this paper, some monotonicity and concavity results of several functions involving the psi and polygamma functions are proved, and then some known inequalities are extended and generalized.
In the note, the functions $\abs{ψ^{(i)}(e^x)}$ for $i\in\mathbb{N}$ are proved to be sub-additive on $(\lnθ_i,\infty)$ and super-additive on $(-\infty,\lnθ_i)$, where $θ_i\in(0,1)$ is the unique root of equation $2\abs{ψ^{(i)}(θ)}=\abs{ψ^{(i)}(θ^2)}$.
In this paper, we sharpen and generalize Shafer's inequality for the arc tangent function. From this, some known results are refined.
In this paper, we sharpen and generalize Carlson's double inequality for the arc cosine function.
In this paper, two sharp inequalities for bounding the psi function $ψ$ and the harmonic numbers $H_n$ are established respectively, some results in [I. Muqattash and M. Yahdi, \textit{Infinite family of approximations of the Digamma function}, Math. Comput. Modelling \textbf{43} (2006), 1329\nobreakdash--1336.] are improved, and some remarks are given.
In the present paper, we give two new proofs for the necessary and sufficient condition $α\le1$ such that the function $x^α[\ln x-ψ(x)]$ is completely monotonic on $(0,\infty)$.
In this paper, we provide a concise proof of Oppenheim's double inequality relating to the cosine and sine functions. In passing, we survey this topic.