1. Preliminaries
The generalized distribution series (GDS) are utilized in mathematics, especially in distribution theory. In order to tackle items that might not be considered classical functions, such as Dirac delta functions and the like, distributions are utilized to expand traditional ideas of functions. Non-integrable functions, like Dirac functions, can be included in the distributions, which are mathematical objects that are interpreted as functions. A function or another mathematical model, like a series, can be used to depict a distribution. The generalized distribution series is widely used in particle physics, diffusion and motion mathematical models, and differential equation theory, particularly in equations with Dirac indices.
In Geometric Function Theory, several researchers have obtained new necessary and sufficient conditions associated with some special functions such as the Wright function [
1], Fox–Wright function [
2], generalized Bessel functions [
3], hypergeometric functions [
4], and generalized hypergeometric functions [
5], among others.
Let
D denote the sum of the convergent series of the form
where
for all
.
Recently, some researchers such as Porwal [
6], Güney and Yıldızhan [
7], Kota [
8], Kota and El-Ashwah [
9], Yalçın et al. [
10] and Porwal and Murugusundaramoorthy [
11] have established a relationship between the subclasses of univalent functions and GDS given by (
2).
In [
12], Porwal suggested extending the discrete probability distribution using the probability mass function, which is provided by
Obviously, and
Furthermore, he established the following series:
This series clearly converges for
. A number of well-known discrete probability distributions can be obtained by specializing the values of
(see [
12]). (I confirm)
Using the coefficients as the generalized distribution probabilities, and taking into account Equations (
1) and (
2) above, we obtain the following:
and
The functions
and
are defined as follows:
and
Let
A be the class of analytic and univalent functions
ℏ of the form
such that
Additionally, denote by
the subclass of
A of functions of the form
Now, by the convolution product
we define the linear operator
as follows:
Definition 1 ([
13]).
A function is said to be in the subclass if and only ifwhere and Remark 1. For some , , and specialization for the coefficients and η in Definition 1, we obtain the following subclasses studied by Kota and El-Ashwah [9]: - 1.
if and only if - 2.
if and only if - 3.
if and only if - 4.
if and only if - 5.
if and only if
Remark 2. For some , , and specialization for the coefficients and η in Definition 1, we obtain the following subclasses studied by Yalçın et al. [10]: - 1.
if and only if - 2.
if and only if
Remark 3. We observe that our class includes, as its special cases, various other classes that were introduced and studied in several works, such as the subclasses TG and TK [14], T and [15], Sp and [16], [17], [18] and [19], among other subclasses. The organization of this paper will be as follows: In
Section 2, we give a sufficient and necessary condition for the generalized distribution series
to be in the inclusive subclass
. The inclusion relation
will be proven in
Section 3. In
Section 4, we give a sufficient and necessary condition for the integral operator
to be in the subclass
. In the last section of this paper, we provide a number of specific corollaries, which improve the existing ones in some recent works.
2. Necessary and Sufficient Condition
In this section, we give the following necessary and sufficient condition for the function to be in the inclusive subclass
Theorem 1. If and then if and only if Proof. To prove that
, from Definition 1, it suffices to show that
Now,
But this expression is bounded above by
if and only if (
5) holds. Thus, the proof is complete. □
3. Inclusion Properties
A function
is said to be in the subclass
if it satisfies the inequality (Dixit and Pal [
20]).
Note that, if
and
, then we obtain the subclass of functions
satisfying the following inequality (Caplinger and Causey [
21]):
Lemma 1 ([
20]).
If is of form (3), thenThe result is sharp. Theorem 2. If , and then if Proof. Let
ℏ be of the form (
3), belonging to the subclass
. By Definition 1, it suffices to show that
Since
ℏ, then by Lemma 1, we obtain
Hence, the condition is obtained if the inequality (
6) is satisfied. □
4. An Integral Operator
Theorem 3. If and then if and only if Proof. By Definition 1, it suffices to show that
Hence, the condition is obtained if the inequality (
7) is satisfied. □
5. Corollaries and Special Cases
The specialization of the parameters and in our theorems lead to many results, some of which have been examined by numerous authors. For instance, the following.
Let
and
in Theorem 1. Thus, we obtain the following corollary, which is due to Kota and El-Ashwah ([
9], Theorem 2.1).
Corollary 1. If then if and only if Let
and
in Theorem 1. Thus, we obtain the following corollary, which is due to Kota and El-Ashwah ([
9], Theorem 2.2).
Corollary 2. If then if and only if Let
and
in Theorem 1. Thus, we obtain the following corollary, which is due to Kota and El-Ashwah ([
9], Theorem 2.3).
Corollary 3. If then if and only if Let
and
in Theorem 1. Thus, we obtain the following corollary, which is due to Kota and El-Ashwah ([
9], Theorem 2.5).
Corollary 4. If then if and only if Let
in Corollary 4; thus, we obtain the following corollary, which is due to Kota and El-Ashwah ([
9], Theorem 2.4).
Corollary 5. If then if and only if Let
and
in Theorem 1. Thus, we obtain the following corollary, which is due to Yalçın et al. [
10] (Theorem 2.1).
Corollary 6. If then if Let
and
in Theorem 1. Thus, we obtain the following corollary, which is due to Yalçın et al. [
10] (Theorem 2.2).
Corollary 7. If then if Let
and
in Theorem 3. Thus, we obtain the following two corollaries, which are due to Yalçın et al. [
10] (Theorem 3.1).
Corollary 8. If then if Remark 4. Note that
- 1.
By taking the results of the aforementioned theorems reduce to the results for te Poisson distribution series;
- 2.
By taking then the results of the aforementioned theorems reduce to the results for the confluent hypergeometric distribution series;
- 3.
By taking then the results of the aforementioned theorems reduce to the results for the hypergeometric distribution-type series;
- 4.
By taking then the results of the aforementioned theorems reduce to the results for the Mittag–Leffler-type Poisson distribution series;
- 5.
By taking in Corollary 2, then we have the results obtained by Lashin et al. [22] (Theorem 7); - 6.
By taking and in Corollary 2, then we have the results of Lashin et al. [22] (Corollary 8); - 7.
By taking in Corollary 3, then we have the results of Lashin et al. [22] (Theorem 9); - 8.
By taking and in Corollary 3, then we have the results of Frasin [23] (Corollary 5.1); - 9.
By taking in Corollary 5, then we have the results of Lashin et al. [22] (Theorem 9); - 10.
If we put , and , , respectively, then we obtain the necessary and sufficient conditions for functions in the classes TG and TK obtained by Porwal [6]; - 11.
If we put , and , , respectively, then we obtain the necessary and sufficient conditions for functions in the classes T and C obtained by Porwal [12]; - 12.
If we put , and , , respectively, then we obtain the necessary and sufficient conditions for functions in the classes Sp and UCV obtained by Porwal and Murugusundaramoorthy [11]; - 13.
If we put , then we obtain the necessary and sufficient conditions for functions in the class Lθ obtained by Kota [8]; - 14.
If we put , and , respectively, then we obtain the necessary and sufficient conditions for functions in the classes S and K obtained by Güney and Yıldızhan [7].
6. Conclusions
In this paper, we have derived some necessary and sufficient conditions for the generalized distribution series to be in the inclusive subclass and the generalized distribution series and the integral operator to be in this subclass . Additionally, we have provided a number of specific corollaries, some of which improve some results available in the literature. This work encourages researchers to find new necessary and sufficient conditions for functions defined by the generalized distribution series or other special functions to be in the subclass .
Author Contributions
Conceptualization and methodology, T.A.-H. and B.F.; validation and formal analysis, T.A.-H.; investigation and resources, I.A.; data curation, writing—review and editing, B.F.; visualization and supervision, I.A. All authors have read and agreed to the published version of the manuscript.
Funding
This work was supported and funded by the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University (IMSIU) (grant number IMSIU-DDRSP2502).
Data Availability Statement
Data are contained within the article.
Conflicts of Interest
The authors declare that they have no conflicts of interest.
References
- Raina, R.K. On univalent and starlike Wright’s hypergeometric functions. Rend. Semin. Mat. Univ. Padova 1996, 95, 11–22. [Google Scholar]
- Chaurasia, V.B.L.; Parihar, H.S. Certain sufficiency conditions on Fox–Wright functions. Demonstr. Math. 2008, 41, 813–822. [Google Scholar]
- Baricz, A. Generalized Bessel Functions of the First Kind; Springer: Berlin, Germany, 2010. [Google Scholar]
- Ponnusamy, S.; Ronning, F. Starlikeness properties for convolution involving hypergeometric series. Ann. Univ. Mariae Curie-Skłodowska Sec. A 1998, 16, 141–155. [Google Scholar]
- Gangadharan, A.; Shanmugam, T.N.; Srivastava, H.M. Generalized hypergeometric functions associated with k-uniformly convex functions. Comput. Math. Appl. 2002, 44, 1515–1526. [Google Scholar] [CrossRef]
- Porwal, S. Mapping properties of certain subclasses of analytic functions associated with generalized distribution series. Appl. Math. E-Notes 2020, 20, 39–45. [Google Scholar]
- Güney, H.Ö.; Yıldızhan, B. Certain subclasses of spirallike univalent functions related with generalized distribution series. Afrika Mat. 2022, 33, 16. [Google Scholar] [CrossRef]
- Kota, W.Y. Some application of a generalized distribution series on certain class of analytic functions. Surv. Math. Appl. 2023, 18, 135–148. [Google Scholar]
- Kota, W.Y.; El-Ashwah, R.M. Sufficient and necessary conditions for the generalized distribution series to be in subclasses of univalent functions. Ukr. Math. J. 2024, 75, 1549–1560. [Google Scholar] [CrossRef]
- Yalçın, S.; Marimuthu, K.; Uma, J. An application of generalized distribution series on certain subclasses of univalent functions. Bol. Soc. Mat. Mex. 2024, 30, 1–12. [Google Scholar] [CrossRef]
- Porwal, S.; Murugusundaramoorthy, G. An application of generalized distribution series on certain classes of univalent functions associated with conic domains. Surv. Math. Its Appl. 2021, 16, 223–236. [Google Scholar]
- Porwal, S. Generalized distribution and its geometric properties associated with univalent functions. J. Complex Anal. 2018, 2018, 8654506. [Google Scholar] [CrossRef]
- Al-Hawary, T.; Frasin, B.A.; Aldawish, I. Applications of generalized hypergeometric distribution on comprehensive families of analytic functions. Symmetry 2024, 16, 2851. [Google Scholar] [CrossRef]
- Thulasiram, T.; Suchithra, K.; Sudharsan, T.V.; Murugusundaramoorthy, G. Some inclusion results associated with certain subclass of analytic functions involving Hohlov operator. Rev. R. Acad. Cienc. Exactas Fis. Nat. Ser. A Math. 2014, 108, 711–720. [Google Scholar] [CrossRef]
- Altintas, O.; Owa, S. On a subclass of certain starlike functions with negative coefficients. Pusan Kyongnam Math. 1988, 4, 41–56. [Google Scholar]
- Bharati, R.; Parvatham, R.; Swaminathan, A. On subclasses of uniformly convex functions and corresponding class of starlike functions. Tamkang J. Math. 1997, 28, 17–32. [Google Scholar] [CrossRef]
- Aouf, M.K. On certain subclass of analytic p-valent functions of order alpha. Rend. Mat. App. 1988, 7, 89–104. [Google Scholar]
- Murugusundaramoorthy, G. Subordination results for spiral-like functions associated with the Srivastava-Attiya operator. Integral Transforms Spec. Funct. 2012, 23, 97–103. [Google Scholar] [CrossRef]
- Murugusundaramoorthy, G. Certain subclasses of spirallike univalent functions related with pascal distribution series. Moroc. J. Pure Appl. Anal. 2021, 7, 312–323. [Google Scholar] [CrossRef]
- Dixit, K.K.; Pal, S.K. On a class of univalent functions related to complex order. Indian J. Pure Appl. Math. 1995, 26, 889–896. [Google Scholar]
- Caplinger, T.R.; Causey, W.M. A class of univalent functions. Proc. Am. Math. Soc. 1973, 39, 357–361. [Google Scholar] [CrossRef]
- Lashin, A.Y.; Badghaish, A.O.; Bajamal, A.Z. The sufficient and necessary conditions for the Poisson distribution series to be in some subclasses of analytic functions. J. Funct. Spaces 2022, 1, 1–6. [Google Scholar] [CrossRef]
- Frasin, B.A. Poisson distribution series on a general class of analytic functions. Acta Comment. Univ. Tartu. Math. 2020, 24, 241–251. [Google Scholar] [CrossRef]
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