Results 51 to 60 of about 1,333 (181)

On a Subclass of Starlike Functions

Rocky Mountain Journal of Mathematics, 1994
Let \(A\) denote the class of functions \(f(z)= z+ \sum^ \infty_{k= 2} a_ k z^ k\) analytic in the unit disk \(D\), \(S\) and \(S^*\) denote the usual subclasses of univalent and starlike functions. For \(\beta< 1\) let \[ R(\beta)= \{ f\in A: \text{Re}(f'(z)+ zf''(z))> \beta,\;z\in D\}\text{ and } \beta_{S^*}= \inf\{\beta: R(\beta)\subset S^*\}. \] In
openaire   +2 more sources

Starlike Functions With Respect to a Boundary Point Connected With Bounded Radius Rotation

Journal of Function Spaces, Volume 2026, Issue 1, 2026.
In the current article, we introduce a new subclass of univalent function Gμ with bounded radius rotation. For this new class, the authors establish many interesting relations between these classes and existing classes. Furthermore, authors try to find coefficient estimations for this new subclass.
Alhanouf Alburaikan, Prathviraj Sharma, S. Sivasubramanian, Jongsuk Ro, Sheza M. El-Deeb, Abdul Rauf Khan   +5 more
wiley   +1 more source

Some Remarks on Ozaki, Ono and Umezawa’s Results

Mathematics
Recall that in On a general second order derivative, Sci. Rep. Tokyo Kyoiku Daigaku A, 5(124–127)(1956), 111–114, Ozaki, Ono and Umezawa proved a result that if f(z) is analytic and satisfies |f″(z)|
Mamoru Nunokawa, Hitoshi Saitoh, Janusz Sokół, Edyta Trybucka   +3 more
doaj   +1 more source

Sufficient Conditions for Janowski Starlikeness [PDF]

International Journal of Mathematics and Mathematical Sciences, 2007
LetA,B,D,E∈[−1,1]and letp(z)be an analytic function defined on the open unit disk,p(0)=1. Conditions onA,B,D, andEare determined so that1+βzp'(z)being subordinated to(1+Dz)/(1+Ez)implies thatp(z)is subordinated to(1+Az)/(1+Bz). Similar results are obtained by considering the expressions1+β(zp'(z)/p(z))and1+β(zp'(z)/p2(z)).
Rosihan M. Ali, V. Ravichandran, N. Seenivasagan   +2 more
openaire   +3 more sources

Coefficient Inequalities Related With Apple‐Like Functions

Journal of Function Spaces, Volume 2026, Issue 1, 2026.
Several subfamilies of Ma and Minda starlike and convex functions have been examined differently through individual generating functions in the literature. However, little or no effort has been devoted to subfamily arising from the product of these generating functions.
Aiman Sana, Afis Saliu, Sadia Riaz, Yufeng Xu   +3 more
wiley   +1 more source

Certain Geometric Investigations of Three Normalized Bessel-Type Functions of a Complex Variable

Mathematics
We recall the normalized forms for the three Bessel-type functions; these functions are the Bessel function, Lommel function, and Struve function of the first kind. By using convolution, we define normalized forms.
Rabab Alyusof, Shams Alyusof, Rabha M. El-Ashwah, Alaa H. El-Qadeem   +3 more
doaj   +1 more source

Properties of a new integral operator

Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2016
In this paper, we derive sufficient conditions for the univalence, star- likeness, convexity and some other properties in the class N (ρ) ; for a new integral operator defined on the space of normalized analytic functions in the open unit disk.
Bucur Roberta, Andrei Loriana, Breaz Daniel   +2 more
doaj   +1 more source

On Second Hankel Determinant of the Class of Biunivalent Beta‐Convex Functions Related to a Five‐Leaf Domain

Journal of Function Spaces, Volume 2026, Issue 1, 2026.
In geometric function theory and complex analysis, analytic functions exhibiting geometric symmetry play a fundamental role. However, investigations concerning multileaf domains, particularly those with fivefold rotational symmetry, have been relatively limited.
Suad Al-Mayyahi, Sheza M. El-Deeb, Mohammad El-Ityan, Dalal Alhwikem, Feras Yousef   +4 more
wiley   +1 more source

Unified Approach of the Logarithmic Coefficient Bounds for the Class of Bazilevic˘ Functions

Journal of Function Spaces, Volume 2026, Issue 1, 2026.
The investigation of logarithmic coefficients in the theory of univalent functions began with Milin, who demonstrated their importance for understanding geometric features of these mappings through their connection with the Taylor coefficients hm. If S denotes the family of univalent functions on the unit disk D with the expansion hz=z+∑m=2∞hmzm, the ...
Ebrahim Analouei Adegani, Nafya Hameed Mohammed, Teodor Bulboacă, Giovanni Di Fratta   +3 more
wiley   +1 more source

On subordination for certain subclass of analytic functions

International Journal of Mathematics and Mathematical Sciences, 1997
In the present paper the class Pn[α,M] consisting of functions f(z)=z+∑k=n+1∞akzz(n≥1), which are analytic in the unit disc E={z:|z|
Liu Jinlin
doaj   +1 more source