Abstract
In the z- domain, differential subordination is a complex technique of geometric function theory based on the idea of differential inequality. It has formulas in terms of the first, second and third derivatives. In this study, we introduce some applications of the third-order differential subordination for a newly defined linear operator that includes -Generalized-Hurwitz–Lerch Zeta functions (GHLZF). These outcomes are derived by investigating the appropriate classes of admissible functions.
Keywords:
holomorphic function; univalent function; p-valent function; convolution product; ξ-Generalized Hurwitz–Lerch Zeta function; differential subordination; admissible functions MSC:
30C45; 33C10; 30C80
1. Introduction and Terminology
Complex Function Theory (CFT) is a mathematical branch dating back to the 18th century. It investigates the functions of complex numbers. This branch has attracted the concern of several researchers. Among the remarkable names are Euler, Gauss, Riemann, Cauchy and others. It has numerous implementations in diverse fields of mathematics and science. These functions have many interesting properties that are not owned by real-valued functions. For instance, infinitely differentiable functions, holomorphic functions, every holomorphic function in the open unit disk can be represented as a Taylor series, conformal functions (that is, they preserve angles when ), line integrals, and all types of handy formulas. The considerable area in CFT is the Geometric Function Theory (GFT). The study of GFT includes investigating the interaction between the analytical properties of the complex holomorphic function and the geometrical properties of the image domain. Riemann [1] in 1851 introduced the first major result in GFT named the Riemann Mapping Theorem. Later, in 1907, Koebe [2] was a prominent scientist who studied the univalent functions in the open unit disk. Thereafter, in 1912, Koebe [3] presented a modified version of the Riemann’s mapping theorem by utilized univalent functions. The theory tends towards the principle of “univalent” and “holomorphic”, Riemann’s mapping theorem plays a significant role in the collection of both principles. This synthesis interprets the formula of a domain where the complex functions being defined, for details see [1,4].
On the other hand, differential inequality theory (inequalities including derivatives of functions) impacted the development of GFT due to it giving much information regarding the behavior of the holomorphic function. Further, there are many differential implications in which characterization of a holomorphic function is settled by a differential condition. For instance, the Noshiro–Warschawski theorem states that for a holomorphic function in the unit disk, implies that f is univalent function in the unit disk. Most of the known differential implications dealt with real-value inequalities that involved the absolute value, the imaginary part, or the real part of a complex function [4].
The principle of subordination is central to the theory of differential subordination of complex-valued function which is the generalizing the formula of differential inequality of real-valued function. Its origins back to Lindelöf [4] in 1909, though Littlewood ([5,6]) and Rogosinski ([7,8]) posed the term and examined the basic outcomes regarding subordination. This principle, as an advantageous tool, displays its importance to unify the presentation of several geometric classes in addition to achieving sandwich-type outcomes.
The methods of differential subordination are employed to study upper bounds for holomorphic functions in the unit disk. This technique inspired numerous researchers to work in GFT. The implementations and extensions of differential subordination theory have been developed in this theme and diverse other fields, such as functions of several complex variables, integral operator theory, meromorphic function theory, harmonic functions theory, differential equations and partial differential equations. Many papers handled the first-order and second-order differential subordination methods, but few articles handled the third-order differential subordination method. In 1935, Goluzin [9] studied the first significant outcome that includes the first-order differential subordination. Afterwards, Suffridge [10] in 1970 and Robinson [11] in 1947 discussed further successive investigations into first-order differential subordination. Later, in 1981, Miller and Mocanu [12] provided a systematic study of the theory of differential subordination. In 1985 [13] and 1987 [14], they evolved and studied several interesting outcomes on this theory. Next, numerous important studies were presented by Miller and Mocanu ([15,16,17]). In 1992, Ponnusamy and Juneja [18] considered the third-order inequalities and subordination. After that, in 2000, Miller and Mocano in their monograph [19] provided a marvelous and extensive discussion on this theory with numerous implementations.
In 2011, Antonino and Miller [20] investigated and extended the second-order differential subordination to the third-order case. Several authors provided fruitful implementations in the same direction of study. For their contributions, Tang et al. [21] considered some third-order differential subordination outcomes for meromorphically p-valent functions associated with the certain linear operator. At the same time, Tang and Deniz [22] studied a similar problem for holomorphic functions, involving the generalized Bessel functions. In 2015, Farzana et al. [23] introduced several third-order differential subordination outcomes for holomorphic functions associated with the fractional derivative operator. Related to this period, Tang et al. [24] used third-order differential subordination methods of holomorphic functions associated with generalized Bessel functions to yield sandwich-type outcomes containing this operator. In the same year, Ibrahim et al. [25] established some third-order differential subordination outcomes for holomorphic functions associated with a fractional integral operator (Carlson–Shaffer operator type). Subsequently, the problems of the third-order differential subordination were studied by El-Ashwah and Hassan [26], El-Ashwah and Hassan [27], Attiya et al. ([28,29]), Srivastava et al. [30] and Gochhayat and Prajapati [31]. Many of the studies have not yet been investigated utilizing third-order differential subordination technique. In this investigation, we impose a new generalized Noor-type linear integral operator on the class of p-valent functions by utilizing -Generalized Hurwitz–Lerch Zeta functions (GHLZF). Some outcomes concerning an application of the third-order differential subordination for multivalent functions including operator are studied.
Denote by the open unit disc in the complex plane , and the class of holomorphic functions in . For , let
and suppose that and . Let denote the class of all holomorphic functions in , normalized by the conditions , and of the formula
The subclass of involving holomorphic univalent function is denoted by , [1]. In [4] the concept of subordination between holomorphic functions given as: for two functions and , holomorphic in , the function is said to be subordinate to , or superordinate to in , written , if there is a holomorphic function ℏ in with and for all , such that . In particular, if the function is univalent in , then the following characterization for subordination is gained as:
The natural generalization of holomorphic univalent function is a p-valent (multivalent) function, that is, if for each , the equation has at most p roots in a domain , and if there is such that the equation has exactly p roots in a Domain . Let denote the class involves all p-valent functions in of the form
If is the p-valent function with , then is the holomorphic univalent function, [4].
As one of the most remarkable tools, namely Hadamard (convolution) product, utilizes to formulate assorted operators: differential, integral and convolution operators. The term “Hadamard product” is attributed to Hadamard in 1899 [1] and defined as: for two functions of the form , , their convolution, , is given by
More generally, the convolution product of two functions of the formula , , is the function given by
In 1915, Alexander [32] was the first to introduce a linear integral operator which drafted in terms of the convolution, namely “Alexander operator” as follows: let and be defined as
Later on, in 1965, Libera [33] given another linear integral operator so-called “Libera operator” by the formula
In 1969, Bernardi [34] imposed a more general linear integral operator , for and , as
The operator is called the generalized Bernardi–Libera–Livingston integral operator. For , the operator reduces to the Alexander operator given by Equation (6) and for , it reduces to the Libera operator defined by Equation (7).
Utilizing the convolution technique, in 1975, Ruscheweyh [35] proposed a linear operator as: let and be defined by
For , yields
Further, and . The operator is called the Ruscheweyh derivative of order of .
Corresponding to the Ruscheweyh operator , given by Equation (10), in 1999, Noor [36] considered the following linear operator: let and be defined as
such that
Evidently, . This reverse relationship between the operators and gives a a cause for naming the Noor operator an integral operator. The operator is called as the Noor integral operator of order of .
Analogous to , written by Equation (9), in 2002, Choi, Saigo and Srivastava [37] defined the linear operator , for , and by
such that
The operator is called the Choi–Saigo–Srivastava operator. For and reduces to the Noor integral operator of Equation (11).
In 2002, Liu and Noor [38] provided a linear operator as: for , and defined by
such that
Obviously, and . The operator is an extended Noor integral operator of Equation (11). In addition, the operator is closely related to the Choi–Saigo–Srivastava operator of Equation (12).
The Theory of Hypergeometric Functions (HFT) has been incorporated in GFT. Employing hypergeometric functions in the proof of the famed problem ”Bieberbach conjecture” by de Branges in 1984 [39] has given complex analysts a renewed attention to study the role of special functions. In this regard a lot of implementations and generalizations are found. The study of this theory gained an independent status. The Gauss Hypergeometric Function (GHF), denoted by , was first introduced by Gauss in 1812 [39]. It is given as follows: for and be complex numbers with other than and
where is the Pochhammer symbol given by
Another important special function related to GHF is the incomplete beta function defined (for , ) by
Other generalized Noor-type linear integral operators between classes of holomorphic functions associated with hypergeometric functions and its generalizations have been posed by authors. For instance, Al-Janaby et al. ([40,41]).
Recently, the theory of Hurwitz–Lerch Zeta functions has a fruitful role in the study operators. This theory is developed with numerous implementations and generalizations by various researchers. One may refer to Al-Janaby et al. [42,43], Ghanim [44], Ghanim and Darus [45], Ghanim and Al-Janaby [46], Rǎducanu and Srivastava [47], Srivastava and Attiya [48], Srivastava et al. [49,50], Xing and Jose [51], Choi and Srivastava [52], Milovanovic and Rassias [53] and Rassias and Yang [54,55,56,57].
In terms of the Hurwitz–Lerch Zeta function defined by (see, for example, [58,59,60])
The following new family of the (GHLZF) was considered systematically by Srivastava [61]:
where
and the equality in the convergence condition holds true for suitably bounded values of given by
Definition 1.
The H-function involved in the right-hand side of Equation (17) is the well-known Fox’s H-function ([62], Definition 1.1) (see also [30,63]) defined by
an empty product is interpreted as 1, and are integers such that
and is a suitable Mellin–Barnes type contour separating the poles of the gamma functions
from the poles of the gamma functions
It is worthy of mention here that, by using the fact that ([61], p. 1496, Remark 7)
Equation (17) reduces to the following form:
Definition 2.
The function involved in Equation (19) is the multiparameter extension and generalization of the Hurwitz–Lerch Zeta function introduced by Srivastava et al. ([64], p. 503, Equation (6.2)) defined by
with
In GFT, the third-order differential subordination methodology for holomorphic functions is indicated by Antonion and Miller [20], which is required in this investigation.
Definition 3
([20], Definition 2, p. 441). Let denote the set of holomorphic functions ω that are univalent on the set where
is such that
for . Further, let , and .
Definition 4
([20], Definition 1, p. 440). Let and the function be univalent in . If the function is holomorphic in and satisfies the following third-order differential subordination:
then is called a solution of the differential subordination. A univalent function is called a dominant of the solutions of the differential subordination, or, more simply, a dominant if for all achieving Equation (21). A dominant that achieves for all dominants of Equation (21) is said to be the best dominant.
The class of admissible functions related to differential subordination is presented next.
Definition 5
([20], Definition 2, p. 449). Let Λ be a set in and . The class of admissible functions denoted by consists of those functions that achieves the following admissibility condition:
whenever
and
where and .
The following theorem is a key outcome in third-order differential subordination.
Theorem 1
([20], Definition 2, p. 449). Let with , and let and achieve the following conditions:
where and . If Λ is a set in and
then
2. Imposed Linear Integral Operator
This section considers a new generalized Noor-type linear integral operator for p-valent functions associated with the GHLZF in defined in Equation (17). Setting as follows:
By employing the principle of convolution product of order of GHLZF, we yield
Next, we present a new function given by
such that,
Therefore, from Equation (26), we consider the following linear operator: , which is defined by
Remark 1.
For suitably specializing the parameters of and , the operator defined in Equation (27) can be reduced to various operators previously mentioned. Thus, we have the following special cases:
- For and in Equation (27), we yield the Ruscheweyh operator given in Equation (9).
- For , and , the operator Equation (27) reduce to the Noor operator defined by Equation (11).
- For , , the operator Equation (27), we have the extended Noor operator given by Equation (13).
- For , and , the operator Equation (27) provides the Noor-type integral operator defined by [65].
- For , and , the operator Equation (27) provides the Noor integral operator given in [66].
- For , and , the operator Equation (27) reduce to the generalized Noor-type linear integral operator defined in [67].
- For and , the operator Equation (27) reduce to Alexander operator given in Equation (6).
- For and , the operator Equation (27) is reduced to given by Equation (2).
For convenience, Equation (27) is written as
This operator achieves the differential recurrence relation
where . Throughout this paper, the generalized Noor-type linear integral operator will be denoted by .
3. Differential Subordination with
This section introduces certain appropriate class of admissible functions and studies some third-order differential subordination outcomes for the operator defined by Equation (27).
Definition 6.
Let be a set in and . The class of admissible functions consists of those functions that satisfy the following admissibility condition:
whenever
and
where and .
Theorem 2.
Let . If and achieve the following conditions:
and
then
Proof.
Define the following holomorphic function in by
Further computations show that
and
Define the parameters and as:
and
Now, we define the transformation as follows:
Therefore, Equation (31) becomes
We also note that
Hence, the admissibility condition for in Definition 8 is equivalent to the admissibility condition of as given in Definition 5 and by Theorem 1, we obtain
The proof of Theorem 2 is complete. □
If is a simply connected domain, then for some conformal mapping of onto . In this case the class is written as . The following outcome is a directly consequence of Theorem 2.
Theorem 3.
Let . If and achieve the following condition (28) given as follows:
and
then
The next outcome is an extension of Theorem 3 to the case where the behavior of on is not known.
Corollary 1.
Let and let be univalent in . Let for some where . If achieves
and
then
where and .
Proof.
By utilizing Theorem 3, we have . Then we get the outcome from . □
The next outcome is an immediate consequence of Corollary 1.
Corollary 2.
Let and let be univalent in . Let for some where . If achieves
and
then
where and .
The following outcome gives the best dominant of the differential subordination of Equation (40).
Theorem 4.
Let be univalent in . Let . Suppose that the differential equation:
has a solution with which achieves Equation (30). If achieves Equation (44) and
is holomorhic in , then
and is the best dominant.
Proof.
In the case and in view of Definition 8, the class of admissible functions denoted by is defined below:
Definition 7.
Let be a set in and . The class of admissible functions consists of those functions that achieve the admissibility condition
where and for all real θ and .
Corollary 3.
Let . If achieves the following conditions:
and
then
In the case , for simplification we denote by to the class .
Corollary 4.
Let . If achieves the following conditions
and
then
Corollary 5.
If . If achieves
then
Proof.
Let . Utilizing Corollary 3 with and
We have to find the condition so that that is, the admissibility condition of Equation (48) is achieved. This follows since
The required outcome is obtained. □
Corollary 6.
If . If achieves
then
Proof.
Let . Utilizing Corollary 3 with and
It is enough to show that that is, the admissibility condition of Equation (48) is achieved. This follows since
This completes the proof. □
Corollary 7.
If . If achieves
then
Proof.
Let . Using Corollary 3 with and
It is adequate to show that that is, the admissibility condition of Equation (48) is achieved. This follows since
The required outcome is derived. □
4. Conclusions and Future Directions
In the terms of the -Generalized Hurwitz–Lerch Zeta functions (GHLZF) in the z- domain, a new generalized Noor-type linear integral operator is introduced. This operator was utilized to study new classes of holomorphic functions in . In addition, new applications of the third-order differential subordination outcome that involves this new operator were investigated. The third-order differential inequalities were imposed in this work to show the uppercase of this new generalized Noor-type linear integral operator in .
Author Contributions
H.A.-J. writing the original draft; F.G. and M.D. writing review and editing. All authors have read and agreed to the published version of the manuscript.
Funding
This research was funded by Universiti Kebangsaan Malaysia, grant number GUP-2019-032.
Conflicts of Interest
The authors declare no conflict of interest.
References
- Duren, P.L. Univalent Functions; Springer: New York, NY, USA, 1983. [Google Scholar]
- Koebe, P. Über die Uniformisierung beliebiger analytischer kurven. Nachrichten Ges. Wiss. Göttingen. Math. Phys. Kl. 1907, 1907, 191–210. [Google Scholar]
- Koebe, P. Über eine neue Methode der konformen Abbildung und Uniformisierung. Nachrichten von der Gesellschaft der Wissenschaften zu Göttingen Mathematisch-Physikalische Klasse 1912, 1912, 844–848. [Google Scholar]
- Goodman, A.W. Univalent Functions, I; Mariner: Tampa, FL, USA, 1983. [Google Scholar]
- Littlewood, J.E. On equalities in the theory of functions. Proc. Lond. Math. Soc. 1925, 23, 481–519. [Google Scholar] [CrossRef]
- Littlewood, J.E. Lectures on the Theory of Functions; Oxford University Press: Oxford, UK; London, UK, 1944. [Google Scholar]
- Rogosinski, W. On subordinate functions. Proc. Camb. Philos. Soc. 1939, 35, 1–26. [Google Scholar] [CrossRef]
- Rogosinski, W. On the coefficients of subordinate functions. Proc. London Math. Soc. 1945, 48, 48–82. [Google Scholar] [CrossRef]
- Goluzin, G.M. On the majorization principle in function theory (Russian). Dokl. Akad. Nauk. SSSR 1953, 42, 647–650. [Google Scholar]
- Suffridge, T.J. Some remarks on convex maps of the unit disk. Duke Math. J. 1970, 37, 775–777. [Google Scholar] [CrossRef]
- Robinson, R.M. Univalent majorants. Trans. Am. Math. Soc. 1947, 61, 1–35. [Google Scholar] [CrossRef]
- Miller, S.S.; Mocanu, P.T. Differential subordinations and univalent functions. Michigan Math. J. 1981, 28, 157–171. [Google Scholar] [CrossRef]
- Miller, S.S.; Mocanu, P.T. On some classes of first order differential subordinations. Michigan Math. J. 1985, 32, 185–195. [Google Scholar] [CrossRef]
- Miller, S.S.; Mocanu, P.T. Differential subordinations and inequalities in the complex plane. J. Differ. Eqns. 1987, 67, 199–211. [Google Scholar] [CrossRef]
- Miller, S.S.; Mocanu, P.T. The theory and applications of second-order differential subordinations. Studia Univ. Babeş-Bolyai Math. 1989, 34, 3–33. [Google Scholar]
- Miller, S.S.; Mocanu, P.T. A Special Differential Subordination and Its Application to Univalency Conditions. In Current Topics in Analytic Function Theory; World Scientific: Singapore; London, UK, 1992; pp. 171–185. [Google Scholar]
- Miller, S.S.; Mocanu, P.T. Briot-Bouquet differential equations and differential subordinations. Complex Var. 1997, 33, 217–237. [Google Scholar] [CrossRef]
- Ponnusamy, S.; Juneja, O.P. Third-Order Differential Inequalities in the Complex Plane. In Current Topics in Analytic Function Theory; World Scientific: Singapore; London, UK, 1992. [Google Scholar]
- Miller, S.S.; Mocanu, P.T. Differential Subordinations: Theory and Applications; Marcel Dekker: New York, NY, USA, 2000. [Google Scholar]
- Antonino, J.A.; Miller, S.S. Third-order differential inequalities and subordinations in the complex plane. Complex Var. Appl. 2011, 56, 439–454. [Google Scholar] [CrossRef]
- Tang, H.; Srivastiva, H.M.; Li, S.; Ma, L. Third-order differential subordinations and superordination results for meromorphically multivalent functions associated with the Liu-Srivastava Operator. Abstr. Appl. Anal. 2014, 2014, 1–11. [Google Scholar] [CrossRef]
- Tang, H.; Deniz, E. Third-order differential subordinations results for analytic functions involving the generalized Bessel functions. Acta Math. Sci. 2014, 6, 1707–1719. [Google Scholar] [CrossRef]
- Farzana, H.A.; Stephen, B.A.; Jeyaraman, M.P. Certain third-order differential subordination and superordination results of meromorphic multivalent functions. Asia Pacific J. Math. 2015, 2, 76–87. [Google Scholar]
- Tang, H.; Srivastiva, H.M.; Deniz, E.; Li, S.-H. Third-order differential superordination involving the generalized Bessel functions. Bull. Malay. Math. Soc. 2015, 38, 1669–1688. [Google Scholar] [CrossRef]
- Ibrahim, R.W.; Ahmad, M.Z.; Al-Janaby, H.F. The Third-Order Differential Subordination and Superordination involving a fractional operator. Open Math. 2015, 13, 706–728. [Google Scholar] [CrossRef]
- El-Ashwah, R.M.; Hassan, A.H. Some third-order differential subordination and superordination results of some meromorphic functions using a Hurwitz-Lerech Zeta type operator. Ilirias J. Math. 2015, 4, 1–15. [Google Scholar]
- El-Ashwah, R.M.; Hassan, A.A. Third-order differential subordination and superordination results by using Fox-Wright generalized hypergeometric function. Func. Anal. TMA 2016, 2, 34–51. [Google Scholar]
- Attiya, A.A.; Kwon, O.S.; Hyang, P.J.; Cho, N.E. An integrodifferential operator for meromorphic functions associated with the Hurwitz–Lerch Zeta function. Filomat 2016, 30, 2045–2057. [Google Scholar] [CrossRef]
- Rǎducanu, D. Third-order differential subordinations for analytic functions associated with generalized Mittag-Leffler functions. Mediterr. J. Math. 2017, 14, 1–18. [Google Scholar] [CrossRef]
- Srivastava, H.M.; Prajapati, A.; Gochhayat, P. Third-order differential subordination and differential superordination results for analytic functions involving the Srivastava-Attiya operator. Appl. Math. Inf. Sci. 2018, 12, 469–481. [Google Scholar] [CrossRef]
- Gochhayat, P.; Prajapati, A. Applications of third order differential subordination and superordination involving generalized Struve function. Filomat 2019, 33, 3047–3059. [Google Scholar] [CrossRef]
- Alexander, J.W. Functions which map the interior of the unit circle upon simple regions. Ann. Math. 1915, 17, 12–22. [Google Scholar] [CrossRef]
- Libera, R.J. Some classes of regular univalent functions. Proc. Am. Math. Soc. 1965, 16, 755–758. [Google Scholar] [CrossRef]
- Bernardi, S.D. Convex and starlike univalent functions. Trans. Am. Math. Soc. 1969, 135, 429–446. [Google Scholar] [CrossRef]
- Ruscheweyh, S. New criteria for univalent functions. Proc. Am. Math. Soc. 1975, 49, 109–115. [Google Scholar] [CrossRef]
- Noor, K.L. On new classes of integral operators. J. Nat. Geom. 1999, 16, 71–80. [Google Scholar]
- Cho, N.E.; Saigo, M.; Srivastava, H.M. Some inclusion properties of a certain family of integral operators. J. Math. Anal. Appl. 2002, 276, 432–445. [Google Scholar] [CrossRef]
- Liu, J.-L.; Noor, K.I. Some properties of noor integral operator. J. Nat. Geom. 2002, 21, 81–90. [Google Scholar]
- Branges, L.D. A proof of the Bieberbach conjecture. Acta Math. 1984, 154, 137–152. [Google Scholar] [CrossRef]
- Al-Janay, H.F.; Ghanim, F. On Subclass Noor-Type Harmonic Multivalent Functions Based on Hypergeometric Functions. Kragujev. J. Math. 2020, 45, 499–519. [Google Scholar]
- Al-Janaby, H.F.; Ghanim, F.; Ahmad, M.Z. Harmonic Multivalent Functions Associated with an Extended Generalized Linear Operator of Noor-type. J. Nonlinear Funct. Anal. Appl. 2019, 24, 269–292. [Google Scholar]
- Al-Janaby, H.F.; Ghanim, F.; Agarwal, P. Geometric Studies on Inequalities of Harmonic Functions in a Complex Field Based on ξ-Generalized Hurwitz–Lerch Zeta Function. Iran. J. Math. Sci. Inform. 2020. accepted. [Google Scholar]
- Al-Janay, H.F.; Ghanim, F.; Darus, M. Some Geometric Properties of Integral Operators Proposed by Hurwitz–Lerch Zeta Function. IOP Conf. Ser. J. Phys. Conf. Ser. 2019, 1212, 1–6. [Google Scholar]
- Ghanim, F. Study of a certain subclass of Hurwitz–Lerch zeta function related to a linear operator. Abstr. Appl. Anal. 2013, 2013, 1–7. [Google Scholar] [CrossRef]
- Ghanim, F.; Darus, M. New result of analytic functions related to Hurwitz-zeta function. Sci. World J. 2013, 2013, 1–5. [Google Scholar] [CrossRef]
- Ghanim, F.; Al-Janaby, H.F. A Certain Subclass of Univalent Meromorphic Functions Defined by a Linear Operator Associated with the Hurwitz–Lerch Zeta Function. Rad Hrvat. Akad. Znan. Umjet. Mat. Znan. 2019, 23, 71–83. [Google Scholar] [CrossRef]
- Rǎducanu, D.; Srivastava, H.M. A new class of analytic functions defined by means of a convolution operator involving the Hurwitz–Lerch zeta function. Integr. Trans. Spec. Funct. 2007, 18, 933–943. [Google Scholar] [CrossRef]
- Srivastava, H.M.; Attiya, A.A. An integral operator associated with the Hurwitz–Lerch zeta function and differential subordination. Integr. Trans. Spec. Funct. 2007, 18, 207–216. [Google Scholar] [CrossRef]
- Srivastava, H.M.; Gaboury, S.A.; Ghanim, F. Certain subclasses of meromorphically univalent functions defined by a linear operator associated with the λ-generalized Hurwitz–Lerch zeta function. Integr. Transf. Spec. Funct. 2015, 26, 258–272. [Google Scholar] [CrossRef]
- Srivastava, H.M.; Gaboury, S.A.; Ghanim, F. Some further properties of a linear operator associated with the λ-generalized Hurwitz–Lerch zeta function related to the class of meromorphically univalent functions. Appl. Math. Comput. 2015, 259, 1019–1029. [Google Scholar]
- Xing, S.C.; Jose, L.L. A note on the asymptotic expansion of the Lerch’s transcendent. Integr. Trans. Spec. Funct. 2019, 30, 844–855. [Google Scholar]
- Choi, J.; Srivastava, H.M. The Multiple Hurwitz Zeta Function and the Multiple Hurwitz-Euler Eta Function. Taiwan J. Math. 2011, 15, 501–522. [Google Scholar] [CrossRef]
- Milovanovic, G.V.; Rassias, M.T. (Eds.) Analytic Number Theory, Approximation Theory and Special Functions—In Honor of Hari M. Srivastava; Springer: Basel, Switzerland, 2014. [Google Scholar]
- Rassias, M.T.; Yang, B. On an Equivalent Property of a Reverse Hilbert-Type Integral Inequality Related to the Extended Hurwitz-Zeta Function. J. Math. Inequal. 2019, 13, 315–334. [Google Scholar] [CrossRef]
- Rassias, M.T.; Yang, B. On a Hilbert-type integral inequality related to the extended Hurwitz zeta function in the whole plane. Acta Appl. Math. 2019, 160, 67–80. [Google Scholar] [CrossRef]
- Rassias, M.T.; Yang, B. Equivalent properties of a Hilbert-type integral inequality with the best constant factor related to the Hurwitz zeta function. Ann. Funct. Anal. 2018, 9, 282–295. [Google Scholar] [CrossRef]
- Rassias, M.T.; Yang, B.; Raigorodskii, A. Two Kinds of the Reverse Hardy-Type Integral Inequalities with the Equivalent Forms Related to the Extended Riemann Zeta Function. Appl. Anal. Discret. Math. 2018, 12, 273–296. [Google Scholar] [CrossRef]
- Srivastava, H.M.; Choi, J. Series Associated with Zeta and Related Functions; Kluwer Academic Publishers: Dordrecht, Germany, 2001. [Google Scholar]
- Srivastava, H.M. Some formulas for the Bernoulli and Euler polynomials at rational arguments. Math. Proc. Camb. Philos. Soc. 2000, 129, 77–84. [Google Scholar] [CrossRef]
- Srivastava, H.M.; Choi, J. Zeta and q-zeta Functions and Associated Series and Integrals; Elsevier Science Publishers: Amsterdam, The Netherland, 2012. [Google Scholar]
- Srivastava, H.M. A new family of the λ-generalized Hurwitz–Lerch zeta functions with applications. Appl. Math. Inf. Sci. 2014, 8, 1485–1500. [Google Scholar] [CrossRef]
- Mathai, A.M.; Saxena, R.K.; Haubold, H.J. The H-function: Theory and applications; Springer: New York, NY, USA, 2010. [Google Scholar]
- Srivastava, H.M.; Gupta, K.C.; Goyal, S.P. The H-functions of One and Two Variables with Applications; South Asian Publishers: New Delhi, India, 1982. [Google Scholar]
- Srivastava, H.M.; Gaboury, S.; Tremblay, R. New relations involving an extended multiparameter Hurwitz–Lerch zeta function with applications. Int. J. Anal. 2014, 2014, 1–14. [Google Scholar] [CrossRef]
- Cho, N.E.; Kwon, O.S.; Srivastava, H.M. Inclusion relationships and argument properties for certain subclasses of multivalent functions associated with a family of linear operators. J. Math. Anal. Appl. 2004, 292, 470–483. [Google Scholar] [CrossRef]
- Noor, K.L. Integral operators defined by convolution with hypergeometric functions. Appl. Math. Comput. 2006, 182, 1872–1881. [Google Scholar] [CrossRef]
- Darus, M.; Ibrahim, R.W. Integral operator defined by convolution product of hypergeometric functions. Int. J. Nonlinear Sci. 2012, 13, 153–157. [Google Scholar]
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).