Cristinel Mortici
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Cristinel Mortici has a total of 42 co-authors. Here are the top co-authors by number of shared publications:
- Chao-Ping Chen
Henan Polytechnic University
9 shared publications - Branko Malesevic
School of Electrical Engineering, University of Belgrade, Bulevar kralja Aleksandra 73, 11000 Belgrade, Serbia
7 shared publications - Yue Hu
School of Mathematics and Information Science Henan Polytechnic University 454000 Jiaozuo Henan China
6 shared publications - Feng Qi
School of Mathematics and Physics, Hulunbuir University, Hulunbuir 021008, China
5 shared publications - Mihai Monea
National College ”Decebal”, Deva, Romania
5 shared publications Chao-Ping Chen
School of Mathematics and Informatics, Henan Polytechnic University, Jiaozuo City, China
4 shared publications
Latest Publications
- Open Access
- 1 September 2026
- Published by Universidad de La Frontera in Cubo (Temuco)
- Vol. 28 (3) , 503-522
Inequalities, asymptotic expansions and complete monotonicity properties related to the gamma and digamma functions
The quotient of two gamma functions has the following known asymptotic expansion: \(\displaystyle \frac{\Gamma(x+a)}{\Gamma(x+b)}\sim x^{a-b}\sum_{k=0}^{\infty}\binom{a-b}{k}B_{k}^{(a-b+1)}(a)\,x^{-k}\quad(x\to\infty),\) where \(B_{k}^{(\nu)}(x)\) denotes the generalized Bernoulli polynomials. In this article, without using these generalized Bernoulli polynomials \(B_{k}^{(\nu)}(x)\), we present two asymptotic expansions and a recurrence relation for determining the coefficients of each asymptotic expansion related to the quotient \(\frac{\Gamma(x+a)}{\Gamma(x+b)}\) of two gamma functions. Let \(\displaystyle \Omega_{n}:=\frac{\pi^{n/2}}{\Gamma\left(\frac{n}{2}+1\right)},\quad n\in\mathbb{N}\) be the volume of the unit ball in \(\mathbb{R}^{n}\). We establish a sharp two-sided inequality for the quotient \(\frac{\Omega_{n-1}}{\Omega_{n}}\). We also present a complete monotonicity property for the Nielsen's \(\beta\)-function, which extends a known result due to Matejíčka.- 1 September 2026
- Published by Universidad de La Frontera in Cubo (Temuco)
- Vol. 28 (3) , 503-522
Open AccessInequalities, asymptotic expansions and complete monotonicity properties related to the gamma and digamma functions
The quotient of two gamma functions has the following known asymptotic expansion: \(\displaystyle \frac{\Gamma(x+a)}{\Gamma(x+b)}\sim x^{a-b}\sum_{k=0}^{\infty}\binom{a-b}{k}B_{k}^{(a-b+1)}(a)\,x^{-k}\quad(x\to\infty),\) where \(B_{k}^{(\nu)}(x)\) denotes the generalized Bernoulli polynomials. In this article, without using these generalized Bernoulli polynomials \(B_{k}^{(\nu)}(x)\), we present two asymptotic expansions and a recurrence relation for determining the coefficients of each asymptotic expansion related to the quotient \(\frac{\Gamma(x+a)}{\Gamma(x+b)}\) of two gamma functions. Let \(\displaystyle \Omega_{n}:=\frac{\pi^{n/2}}{\Gamma\left(\frac{n}{2}+1\right)},\quad n\in\mathbb{N}\) be the volume of the unit ball in \(\mathbb{R}^{n}\). We establish a sharp two-sided inequality for the quotient \(\frac{\Omega_{n-1}}{\Omega_{n}}\). We also present a complete monotonicity property for the Nielsen's \(\beta\)-function, which extends a known result due to Matejíčka. - Open Access
- 30 June 2026
- Published by Springer Nature in Results in Mathematics
- Vol. 81 (5) , 141
Structural Properties, Complete Monotonicity, Bounds, and Analytic Approximations with Bounded Remainders for a Wallis-Type Gamma Ratio
In this paper, we investigate several completely monotonic functions involving the Psi function, which is defined as the logarithmic derivative of the Gamma function. By exploiting the analytic and monotonic properties of these functions, we develop three new approximation formulas for a Wallis-type ratio with bounded remainder terms. These approximations lead to a number of new inequalities that are better than some existing bounds in the literature. Finally, an open problem is proposed concerning the monotonic behavior of the remainder functions arising from the new approximations.
- 30 June 2026
- Published by Springer Nature in Results in Mathematics
- Vol. 81 (5) , 141
Open AccessStructural Properties, Complete Monotonicity, Bounds, and Analytic Approximations with Bounded Remainders for a Wallis-Type Gamma Ratio
In this paper, we investigate several completely monotonic functions involving the Psi function, which is defined as the logarithmic derivative of the Gamma function. By exploiting the analytic and monotonic properties of these functions, we develop three new approximation formulas for a Wallis-type ratio with bounded remainder terms. These approximations lead to a number of new inequalities that are better than some existing bounds in the literature. Finally, an open problem is proposed concerning the monotonic behavior of the remainder functions arising from the new approximations.
- Open Access
- 18 June 2026
- Published by University of Craiova in Annals of the University of Craiova Mathematics and Computer Science Series
- Vol. 53 (1) , 241-246
On the Ghermănescu's sequence
The aim of this work is to establish some properties of the Ghermănescu's sequence.
- 18 June 2026
- Published by University of Craiova in Annals of the University of Craiova Mathematics and Computer Science Series
- Vol. 53 (1) , 241-246
Open AccessOn the Ghermănescu's sequence
The aim of this work is to establish some properties of the Ghermănescu's sequence.
- Open Access
- 29 May 2026
- Published by MDPI AG in Mathematics
- Vol. 14 (11) , 1898
Sharp Arcsine-Type Bounds and Analytic Approximations for the Gauss Lemniscate Sine Function
This paper develops two novel arcsine-type analytic approximation formulas for , the Gauss lemniscate sine function, each equipped with a monotonic and bounded remainder term of order as , which demonstrates the high accuracy of the obtained formulas near the origin. Based on these approximations, we establish several new sharp inequalities valid on the interval . Numerical evidence confirms that the resulting bounds provide improved accuracy compared with existing estimates in the literature, particularly in a neighborhood of the origin.- 29 May 2026
- Published by MDPI AG in Mathematics
- Vol. 14 (11) , 1898
Open AccessSharp Arcsine-Type Bounds and Analytic Approximations for the Gauss Lemniscate Sine Function
This paper develops two novel arcsine-type analytic approximation formulas for , the Gauss lemniscate sine function, each equipped with a monotonic and bounded remainder term of order as , which demonstrates the high accuracy of the obtained formulas near the origin. Based on these approximations, we establish several new sharp inequalities valid on the interval . Numerical evidence confirms that the resulting bounds provide improved accuracy compared with existing estimates in the literature, particularly in a neighborhood of the origin. - Open Access
- 27 February 2026
- Published by MDPI AG in Preprints.org
Some New Properties of the Gamma Function Based on Ramanujan’s Formula and Nemes’ Formula
Ramanujan presented the following approximation formula of the gamma function: \( \Gamma(x+1)\approx\sqrt{\pi}\left( \frac{x}{e}\right) ^{x} \left( 8x^{3}+4x^{2}+x+\frac{1}{30}\right) ^{1/6},\qquad x\to\infty. \) In this paper, we develop Ramanujan's approximation formula to derive a number of complete asymptotic expansions. We also establish several subadditive and superadditive properties of some functions which are related to the gamma function.- 27 February 2026
- Published by MDPI AG in Preprints.org
Open AccessSome New Properties of the Gamma Function Based on Ramanujan’s Formula and Nemes’ Formula
Ramanujan presented the following approximation formula of the gamma function: \( \Gamma(x+1)\approx\sqrt{\pi}\left( \frac{x}{e}\right) ^{x} \left( 8x^{3}+4x^{2}+x+\frac{1}{30}\right) ^{1/6},\qquad x\to\infty. \) In this paper, we develop Ramanujan's approximation formula to derive a number of complete asymptotic expansions. We also establish several subadditive and superadditive properties of some functions which are related to the gamma function. - 21 February 2026
- Published by Springer Nature in Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas
- Vol. 120 (2) , 45
Cusa-type inequalities for trigonometric and hyperbolic functions
- 21 February 2026
- Published by Springer Nature in Revista de la Real Academia de Ciencias Exactas, Fisicas y Naturales. Serie A. Matematicas
- Vol. 120 (2) , 45
Cusa-type inequalities for trigonometric and hyperbolic functions
- Open Access
- 10 January 2026
- Published by Universidad de La Frontera in Cubo (Temuco)
- Vol. 28 (1) , 43–51
Modified convergences to the Euler-Mascheroni constant
We introduce in this paper some new sequences that converge to the Euler-Mascheroni constant. These sequences have a higher convergence rate than the classical one. Further properties are given.
- 10 January 2026
- Published by Universidad de La Frontera in Cubo (Temuco)
- Vol. 28 (1) , 43–51
Open AccessModified convergences to the Euler-Mascheroni constant
We introduce in this paper some new sequences that converge to the Euler-Mascheroni constant. These sequences have a higher convergence rate than the classical one. Further properties are given.
- Open Access
- 1 January 2026
- Published by National Library of Serbia in Applicable Analysis and Discrete Mathematics
- No. 00,p. 15
Advances in Mitrinovic–Adamovic-type inequalities
In this paper, we provide several new Mitrinovic?Adamovic-type inequalities and pose some open problems.
- 1 January 2026
- Published by National Library of Serbia in Applicable Analysis and Discrete Mathematics
- No. 00,p. 15
Open AccessAdvances in Mitrinovic–Adamovic-type inequalities
In this paper, we provide several new Mitrinovic?Adamovic-type inequalities and pose some open problems.
- Open Access
- 30 December 2025
- Published by Valahia University of Targoviste - Journal of Science and Arts in Journal of Science and Arts
- Vol. 25 (4)
IMPROVING THE CLASSICAL CONVERGENCE TO EULER-MASCHERONI SEQUENCE BY MODIFYING THE MIDDLE TERM
The aim of this paper is to introduce a new sequence that converges to Euler-Mascheroni constant. Some inequalities and asymptotic formulas are provided. Finally, some numerical comparisons are given.
- 30 December 2025
- Published by Valahia University of Targoviste - Journal of Science and Arts in Journal of Science and Arts
- Vol. 25 (4)
Open AccessIMPROVING THE CLASSICAL CONVERGENCE TO EULER-MASCHERONI SEQUENCE BY MODIFYING THE MIDDLE TERM
The aim of this paper is to introduce a new sequence that converges to Euler-Mascheroni constant. Some inequalities and asymptotic formulas are provided. Finally, some numerical comparisons are given.
- Open Access
- 30 December 2025
- Published by Valahia University of Targoviste - Journal of Science and Arts in Journal of Science and Arts
- Vol. 25 (4) , 771
NEW CONVERGENT SEQUENCES FOR APPROXIMATING THE EULER-MASCHERONI CONSTANT
In this paper, we present new sequences that offer improved approximations of the Euler-Mascheroni constant. One of the proposed sequences converges to its limit like m^(-8) tends to zero, as m→∞. Furthermore, several new inequalities involving this constant and the Digamma function are established. We also prove that certain functions related to our sequences are completely monotonic. Finally, an open question is posed.
- 30 December 2025
- Published by Valahia University of Targoviste - Journal of Science and Arts in Journal of Science and Arts
- Vol. 25 (4) , 771
Open AccessNEW CONVERGENT SEQUENCES FOR APPROXIMATING THE EULER-MASCHERONI CONSTANT
In this paper, we present new sequences that offer improved approximations of the Euler-Mascheroni constant. One of the proposed sequences converges to its limit like m^(-8) tends to zero, as m→∞. Furthermore, several new inequalities involving this constant and the Digamma function are established. We also prove that certain functions related to our sequences are completely monotonic. Finally, an open question is posed.