Skip to Content

922 Results Found

  • Article
  • Open Access
7 Citations
1,432 Views
11 Pages

8 December 2024

In the study, the authors introduce Qi’s normalized remainder of the Maclaurin power series expansion of the function lnsecx=lncosx; in view of a monotonicity rule for the ratio of two Maclaurin power series and by virtue of the logarith...

  • Article
  • Open Access
1,330 Views
15 Pages

27 May 2024

The beta-logarithmic function substantially generalizes the standard beta function, which is widely recognized for its significance in many applications. This article is devoted to the study of a generalization of the classical beta-logarithmic funct...

  • Article
  • Open Access
5 Citations
2,115 Views
10 Pages

Logarithmic Coefficients Inequality for the Family of Functions Convex in One Direction

  • Ebrahim Analouei Adegani,
  • Ahmad Motamednezhad,
  • Mostafa Jafari and
  • Teodor Bulboacă

The logarithmic coefficients play an important role for different estimates in the theory of univalent functions. Due to the significance of the recent studies about the logarithmic coefficients, the problem of obtaining the sharp bounds for the modu...

  • Article
  • Open Access
25 Citations
3,179 Views
11 Pages

The logarithmic functions have been used in a verity of areas of mathematics and other sciences. As far as we know, no one has used the coefficients of logarithmic functions to determine the bounds for the third Hankel determinant. In our present inv...

  • Article
  • Open Access
16 Citations
2,291 Views
16 Pages

Sharp Bounds of Hankel Determinant on Logarithmic Coefficients for Functions Starlike with Exponential Function

  • Lei Shi,
  • Muhammad Arif,
  • Javed Iqbal,
  • Khalil Ullah and
  • Syed Muhammad Ghufran

Using the Lebedev–Milin inequalities, bounds on the logarithmic coefficients of an analytic function can be transferred to estimates on coefficients of the function itself and related functions. From this fact, the study of logarithmic-related...

  • Article
  • Open Access
12 Citations
2,008 Views
23 Pages

Estimation of the Second-Order Hankel Determinant of Logarithmic Coefficients for Two Subclasses of Starlike Functions

  • Pongsakorn Sunthrayuth,
  • Ibtisam Aldawish,
  • Muhammad Arif,
  • Muhammad Abbas and
  • Sheza El-Deeb

29 September 2022

In our present study, two subclasses of starlike functions which are symmetric about the origin are considered. These two classes are defined with the use of the sigmoid function and the trigonometric function, respectively. We estimate the first fou...

  • Communication
  • Open Access
251 Views
7 Pages

11 February 2026

In this methodological–technical note, in addition to the well-known concepts of logarithms of positive real numbers and operators, we open a path for mathematical treatment of the mathematical concept of the logarithm of a vector. We prove the...

  • Article
  • Open Access
15 Citations
2,659 Views
18 Pages

1 September 2023

In view of a general formula for higher order derivatives of the ratio of two differentiable functions, the authors establish the first form for the Maclaurin power series expansion of a logarithmic expression in term of determinants of special Hesse...

  • Article
  • Open Access
730 Views
21 Pages

Inverse and Logarithmic Coefficient Bounds of Concave Univalent Functions

  • Kuppusami Sakthivel,
  • Nak Eun Cho and
  • Srikandan Sivasubramanian

22 July 2025

The concept of coefficient estimates on univalent functions is one of the interesting aspects explored recently by many researchers. Motivated by this direction, in this present work, we obtain the upper bounds of initial inverse coefficients and log...

  • Article
  • Open Access
2,165 Views
9 Pages

21 September 2021

A class of definite integrals involving a quotient function with a reducible polynomial, logarithm and nested logarithm functions are derived with a possible connection to contact problems for a wedge. The derivations are expressed in terms of the Le...

  • Feature Paper
  • Article
  • Open Access
3 Citations
3,521 Views
12 Pages

We consider a Keller–Segel type chemotaxis model with logarithmic sensitivity and logistic growth. The logarithmic singularity in the system is removed via the inverse Hopf–Cole transformation. We then linearize the system around a constant equilibri...

  • Article
  • Open Access
2,122 Views
29 Pages

16 April 2023

In this paper, first derivatives of the Whittaker function Mκ,μx are calculated with respect to the parameters. Using the confluent hypergeometric function, these derivarives can be expressed as infinite sums of quotients of the digamma and...

  • Article
  • Open Access
16 Citations
2,214 Views
19 Pages

6 June 2022

The purpose of this article is to obtain the sharp estimates of the first four initial logarithmic coefficients for the class BTs of bounded turning functions associated with a petal-shaped domain. Further, we investigate the sharp estimate of Fekete...

  • Article
  • Open Access
8 Citations
3,650 Views
25 Pages

16 March 2022

Generalized numbers, arithmetic operators, and derivative operators, grouped in four classes based on symmetry features, are introduced. Their building element is the pair of q-logarithm/q-exponential inverse functions. Some of the objects were previ...

  • Article
  • Open Access
2 Citations
1,661 Views
19 Pages

15 June 2023

Recently, we have established and used the generalized Littlewood theorem concerning contour integrals of the logarithm of analytical function to obtain new criteria equivalent to the Riemann hypothesis. Later, the same theorem was applied to calcula...

  • Article
  • Open Access
1 Citations
1,417 Views
15 Pages

23 August 2024

Recently, we established and used the generalized Littlewood theorem concerning contour integrals of the logarithm of analytical function to obtain new criteria equivalent to the Riemann hypothesis. The same theorem was subsequently applied to calcul...

  • Article
  • Open Access
2 Citations
2,116 Views
16 Pages

7 January 2023

Recently, we have established and used the generalized Littlewood theorem concerning contour integrals of the logarithm of an analytical function to obtain a few new criteria equivalent to the Riemann hypothesis. Here, the same theorem is applied to...

  • Article
  • Open Access
282 Views
19 Pages

Estimating 2,3-Fold Hankel Determinants, Zalcman Functionals and Logarithmic Coefficients of Certain Subclasses of Holomorphic Functions with Bounded Rotations

  • Farouq Alshormani,
  • Bushra Kanwal,
  • Faiza Attiq,
  • Amr M. Y. Abdelaty,
  • Alina Alb Lupas and
  • Ibrahim S. Elshazly

26 December 2025

The study explores analytic, geometric and algebaraic properties of two subclasses of analytic functions: the class of Bounded Radius Rotation denoted by Rs,ϱ(A,B,z), and the class of Bounded Boundary Rotation denoted by Vs,ϱ(A,B,z), both...

  • Article
  • Open Access
1,669 Views
29 Pages

Optimal Portfolio Analysis Using Power and Natural Logarithm Utility Functions with E-Commerce Data

  • Apni Diyanti,
  • Moch. Fandi Ansori,
  • Susilo Hariyanto and
  • Ratna Herdiana

Determining the optimal portfolio is important in the investment process because it includes the selection of appropriate fund allocation to manage financial risk effectively. Although risk cannot be entirely eliminated, it is managed through strateg...

  • Article
  • Open Access
10 Citations
1,746 Views
10 Pages

14 August 2022

The purpose of this study was to obtain the sharp Hankel determinant H2,1Ff/2 and H2,2Ff/2 with a logarithmic coefficient as entry for the class BT3L of bounded turning functions connected with a three-leaf-shaped domain. In this study, we developed...

  • Article
  • Open Access
46 Citations
4,351 Views
23 Pages

13 July 2021

Seismic fragility analysis is an efficient method to evaluate the structural failure probability during earthquake events. Among the existing fragility analysis methods, the probabilistic seismic demand model (PSDM) and the joint probabilistic seismi...

  • Feature Paper
  • Article
  • Open Access
11 Citations
3,948 Views
26 Pages

26 February 2024

Memristors are state-of-the-art, nano-sized, two-terminal, passive electronic elements with very good switching and memory characteristics. Owing to their very low power usage and a good compatibility to the existing CMOS ultra-high-density integrate...

  • Article
  • Open Access
3 Citations
2,908 Views
6 Pages

30 November 2021

In this paper, we have derived and evaluated a quadruple integral whose kernel involves the logarithm and product of Bessel functions of the first kind. A new quadruple integral representation of Catalan’s G and Apéry’s ζ(3) c...

  • Article
  • Open Access
21 Citations
3,332 Views
14 Pages

23 February 2023

Technology includes hard technology and soft technology. Material technology embodied in production conditions and working conditions such as machinery, equipment and infrastructure is called hard technology, referring to the technology directly used...

  • Article
  • Open Access
3 Citations
2,142 Views
14 Pages

Coefficient Problems for a Class of Univalent Functions

  • Dong Guo,
  • Huo Tang,
  • Zongtao Li,
  • Qingbing Xu and
  • En Ao

12 April 2023

In this paper, a new subclass has been defined as Ω of the univalent function in D={zC:|z|<1}. The central goal of this paper is to determine estimates for logarithmic coefficients, inverse logarithmic coefficients, some cases of the H...

  • Feature Paper
  • Article
  • Open Access
8 Citations
6,037 Views
6 Pages

The derivation of integrals in the table of Gradshteyn and Ryzhik in terms of closed form solutions is always of interest. We evaluate several of these definite integrals of the form 0 log ( 1 ± e α y )...

  • Article
  • Open Access
29 Citations
4,259 Views
12 Pages

Logarithmic Coefficients for Univalent Functions Defined by Subordination

  • Ebrahim Analouei Adegani,
  • Nak Eun Cho and
  • Mostafa Jafari

In this work, the bounds for the logarithmic coefficients γ n of the general classes S * ( φ ) and K ( φ ) were estimated. It is worthwhile mentioning that the given bounds would generalize some of the previo...

  • Article
  • Open Access
12 Citations
66,806 Views
5 Pages

24 November 2019

We present a method using contour integration to evaluate the definite integral of the form 0 log k ( a y ) R ( y ) d y in terms of special functions, where R ( y ) = y m 1 + α y n and k , m...

  • Article
  • Open Access
4 Citations
2,786 Views
21 Pages

25 April 2024

While traditional support vector regression (SVR) models rely on loss functions tailored to specific noise distributions, this research explores an alternative approach: ε-ln SVR, which uses a loss function based on the natural logarithm of t...

  • Article
  • Open Access
6 Citations
1,960 Views
11 Pages

11 May 2024

Starlike and convex functions have gained increased prominence in both academic literature and practical applications over the past decade. Concurrently, logarithmic coefficients play a pivotal role in estimating diverse properties within the realm o...

  • Article
  • Open Access
21 Citations
2,129 Views
12 Pages

14 July 2023

In the paper, by virtue of a derivative formula for the ratio of two differentiable functions and with the help of a monotonicity rule, the authors expand a logarithmic expression involving the sine function into the Maclaurin power series in terms o...

  • Article
  • Open Access
3 Citations
1,689 Views
13 Pages

Logarithmic Coefficients for Some Classes Defined by Subordination

  • Ebrahim Analouei Adegani,
  • Ahmad Motamednezhad,
  • Teodor Bulboacă and
  • Nak Eun Cho

29 March 2023

In this paper, we obtain the sharp and accurate bounds for the logarithmic coefficients of some subclasses of analytic functions defined and studied in earlier works. Furthermore, we obtain the bounds of the second Hankel determinant of logarithmic c...

  • Article
  • Open Access
13 Citations
2,233 Views
15 Pages

5 August 2024

In the paper, (1) in view of a general formula for any derivative of the quotient of two differentiable functions, (2) with the aid of a monotonicity rule for the quotient of two power series, (3) in light of the logarithmic convexity of an elementar...

  • Feature Paper
  • Article
  • Open Access
4 Citations
1,691 Views
24 Pages

27 March 2024

In this paper, exact solutions of semilinear equations having exponential growth in the space variable x are found. Semilinear Schrödinger equation with logarithmic nonlinearity and third-order evolution equations arising in optics with logarith...

  • Article
  • Open Access
2 Citations
1,110 Views
19 Pages

Application of Partial Discrete Logarithms for Discrete Logarithm Computation

  • Dina Shaltykova,
  • Yelizaveta Vitulyova,
  • Kaisarali Kadyrzhan and
  • Ibragim Suleimenov

22 August 2025

A novel approach to constructing an algorithm for computing discrete logarithms, which holds significant interest for advancing cryptographic methods and the applied use of multivalued logic, is proposed. The method is based on the algebraic delta fu...

  • Feature Paper
  • Article
  • Open Access
6 Citations
4,835 Views
40 Pages

In this paper, function approximation is utilized to establish functional series approximations to integrals. The starting point is the definition of a dual Taylor series, which is a natural extension of a Taylor series, and spline based series appro...

  • Article
  • Open Access
2 Citations
3,357 Views
10 Pages

27 January 2022

Using the Dunford–Taylor integral and a representation formula for the resolvent of a non-singular complex matrix, we find the logarithm of a non-singular complex matrix applying the Cauchy’s residue theorem if the matrix eigenvalues are...

  • Article
  • Open Access
2 Citations
2,539 Views
9 Pages

6 September 2021

A quadruple integral involving the logarithmic, exponential and polynomial functions is derived in terms of the Lerch function. Special cases of this integral are evaluated in terms of special functions and fundamental constants. Almost all Lerch fun...

  • Article
  • Open Access
28 Citations
2,870 Views
12 Pages

Certain Coefficient Estimate Problems for Three-Leaf-Type Starlike Functions

  • Lei Shi,
  • Muhammad Ghaffar Khan,
  • Bakhtiar Ahmad,
  • Wali Khan Mashwani,
  • Praveen Agarwal and
  • Shaher Momani

In our present investigation, some coefficient functionals for a subclass relating to starlike functions connected with three-leaf mappings were considered. Sharp coefficient estimates for the first four initial coefficients of the functions of this...

  • Article
  • Open Access
13 Citations
1,935 Views
16 Pages

Problems Concerning Coefficients of Symmetric Starlike Functions Connected with the Sigmoid Function

  • Muhammad Imran Faisal,
  • Isra Al-Shbeil,
  • Muhammad Abbas,
  • Muhammad Arif and
  • Reem K. Alhefthi

21 June 2023

In numerous geometric and physical applications of complex analysis, estimating the sharp bounds of coefficient-related problems of univalent functions is very important due to the fact that these coefficients describe the core inherent properties of...

  • Article
  • Open Access
4 Citations
1,633 Views
12 Pages

Generalized Bounded Turning Functions Connected with Gregory Coefficients

  • Huo Tang,
  • Zeeshan Mujahid,
  • Nazar Khan,
  • Fairouz Tchier and
  • Muhammad Ghaffar Khan

28 May 2024

In this research article, we introduce new family RG of holomorphic functions, which is related to the generalized bounded turning and generating functions of Gregory coefficients. Leveraging the concept of functions with positive real parts, we acqu...

  • Article
  • Open Access
1 Citations
2,086 Views
13 Pages

19 April 2024

Here, we study the extension of p-trigonometric functions sinp and cosp family in complex domains and p-hyperbolic functions sinhp and the coshp family in hyperbolic complex domains. These functions satisfy analogous relations as their classical coun...

  • Article
  • Open Access
3,123 Views
11 Pages

24 August 2024

Determining the exact number of primes at large magnitudes is computationally intensive, making approximation methods (e.g., the logarithmic integral, prime number theorem, Riemann zeta function, Chebyshev’s estimates, etc.) particularly valuab...

  • Article
  • Open Access
7 Citations
1,769 Views
24 Pages

Sharp Coefficient Problems of Functions with Bounded Turnings Subordinated by Sigmoid Function

  • Muhammad Arif,
  • Safa Marwa,
  • Qin Xin,
  • Fairouz Tchier,
  • Muhammad Ayaz and
  • Sarfraz Nawaz Malik

18 October 2022

This study deals with analytic functions with bounded turnings, defined in the disk Od=z:z<1. These functions are subordinated by sigmoid function 21+ez and their class is denoted by BTSg. Sharp coefficient inequalities, including the third...

  • Article
  • Open Access
3 Citations
4,715 Views
22 Pages

10 June 2019

In this work, the Sieve of Eratosthenes procedure (in the following named Sieve procedure) is approached by a novel point of view, which is able to give a justification of the Prime Number Theorem (P.N.T.). Moreover, an extension of this procedure to...

  • Article
  • Open Access
1 Citations
939 Views
14 Pages

29 May 2024

In this paper, we create a new subclass of convex functions given with tangent functions applying the combination of Babalola operators and Binomial series. Moreover, we obtain several important geometric results, including sharp coefficient bounds,...

  • Article
  • Open Access
1 Citations
1,141 Views
32 Pages

On Certain Analytic Functions Associated with Nephroid Function

  • Wahid Ullah,
  • Rabia Fayyaz,
  • Daniel Breaz and
  • Luminiţa-Ioana Cotîrlă

14 February 2025

The normalized analytic function ΦN(z)=1+zz33, which connects the open unit disk onto a bounded domain within the right half of a nephroid-shaped region, is associated with the bounded turning of functions denoted by Rn. It calculates the...

  • Article
  • Open Access
5 Citations
4,786 Views
10 Pages

20 October 2021

We present a method using contour integration to derive definite integrals and their associated infinite sums which can be expressed as a special function. We give a proof of the basic equation and some examples of the method. The advantage of using...

of 19