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In this paper our aim is to show some new inequalities of the Redheffer type for Bessel and modified Bessel functions of the first kind. The key tools in our proofs are some classical results on the monotonicity of quotients of differentiable functions as well as on the monotonicity of quotients of two power series. We also use some known results on the quotients of Bessel and modified Bessel functions of the first kind, and by using the monotonicity of the Dirichlet eta function we prove a sharp inequality for the tangent function. At the end of the paper a conjecture is stated, which may be of interest for further research. [ABSTRACT FROM AUTHOR]

Some Turán type inequalities for Struve functions of the first kind are deduced by using various methods developed in the case of Bessel functions of the first and second kind. New formulas, like Mittag–Leffler expansion, infinite product representation for Struve functions of the first kind, are obtained, which may be of independent interest. Moreover, some complete monotonicity results and functional inequalities are deduced for Struve functions of the second kind. These results complement naturally the known results for a particular case of Lommel functions of the first kind, and for modified Struve functions of the first and second kind. [ABSTRACT FROM AUTHOR]

Geometric properties of the Jackson and Hahn–Exton q -Bessel functions are studied. For each of them, three different normalizations are applied in such a way that the resulting functions are analytic in the unit disk of the complex plane. For each of the six functions we determine the radii of starlikeness and convexity precisely by using their Hadamard factorization. These are q -generalizations of some known results for Bessel functions of the first kind. The characterization of entire functions from the Laguerre–Pólya class via hyperbolic polynomials plays an important role in this paper. Moreover, the interlacing property of the zeros of Jackson and Hahn–Exton q -Bessel functions and their derivatives is also useful in the proof of the main results. We also deduce a necessary and sufficient condition for the close-to-convexity of a normalized Jackson q -Bessel function and its derivatives. Some open problems are proposed at the end of the paper. [ABSTRACT FROM AUTHOR]

Turán, Mitrinović–Adamović and Wilker type inequalities are deduced for regular Coulomb wave functions. The proofs are based on a Mittag–Leffler expansion for the regular Coulomb wave function, which may be of independent interest. Moreover, some complete monotonicity results concerning the Coulomb zeta functions and some interlacing properties of the zeros of Coulomb wave functions are given. [ABSTRACT FROM AUTHOR]

Discussing Ramanujan's Question 294, Karamata established the in-equality... which is the cornerstone of this paper. We generalize the above inequality trans-forming into terms of arctan and artanh. Moreover, we expand the established result to the class of generalized inverse p-trigonometric arctanp and to hyper-bolic artanhp functions. [ABSTRACT FROM AUTHOR]

Lower and upper bounds are deduced for some Jaeger integrals which involve the Bessel functions of the first and second kind. The upper bounds contain some elementary functions as well as incomplete gamma functions, while the lower bounds are expressed also in terms of incomplete gamma functions and are deduced via some known inequalities for Bessel functions of the first and second kinds. [ABSTRACT FROM AUTHOR]

Abstract: Various miscellaneous functional inequalities are deduced for the so-called generalized inverse trigonometric and hyperbolic functions. For instance, functional inequalities for sums, difference and quotient of generalized inverse trigonometric and hyperbolic functions are given, as well as some Grünbaum inequalities with the aid of the classical Bernoulli inequality. Moreover, by means of certain already derived bounds, bilateral bounding inequalities are obtained for the generalized hypergeometric Clausen function. [Copyright &y& Elsevier]

In this paper first we survey the Turán type inequalities and related problems for the Bessel functions of the first kind. Then we extend the known higher order Turán type inequalities for Bessel functions of the first kind to real parameters and we deduce new closed integral representation formulas for the second kind Neumann type series of Bessel functions of the first kind occurring in the study of Turán determinants of Bessel functions of the first kind. At the end of the paper we prove a Turán type inequality for the Bessel functions of the second kind. [ABSTRACT FROM AUTHOR]

Abstract: In this paper our aim is to deduce some Turán type inequalities for -hypergeometric and -confluent hypergeometric functions. In order to obtain the main results we apply the methods developed in the case of classical Kummer and Gauss hypergeometric functions. [Copyright &y& Elsevier]

Some sharp two-sided Turán type inequalities for parabolic cylinder functions and Tricomi confluent hypergeometric functions are deduced. The proofs are based on integral representations for quotients of parabolic cylinder functions and Tricomi confluent hypergeometric functions, which arise in the study of the infinite divisibility of the Fisher-Snedecor F distribution. Moreover, some complete monotonicity results are given concerning Turán determinants of Tricomi confluent hypergeometric functions. These complement and improve some of the results of Ismail and Laforgia (in Constr. Approx. 26:1-9, ). [ABSTRACT FROM AUTHOR]

In this note our aim is to point out that certain inequalities for modified Bessel functions of the first and second kind, deduced recently by Laforgia and Natalini, are in fact equivalent to the corresponding Turán type inequalities for these functions. Moreover, we present some new Turán type inequalities for the aforementioned functions and we show that their product is decreasing as a function of the order, which has an application in the study of stability of radially symmetric solutions in a generalized FitzHugh-Nagumo equation in two spatial dimensions. At the end of this note an open problem is posed, which may be of interest for further research. [ABSTRACT FROM AUTHOR]

Abstract: Complete monotonicity, Laguerre and Turán type inequalities are established for the so-called Krätzel function , defined by where and . Moreover, we prove the complete monotonicity of a determinant function of which entries involve the Krätzel function. [Copyright &y& Elsevier]

Abstract: We present several inequalities for where is the incomplete gamma function. One of our theorems states that the inequalities hold for all nonnegative real numbers if and only if and . Here, denotes the power sum of order t. This extends and complements a result published by Ismail and Laforgia in 2006. [Copyright &y& Elsevier]

In this paper our aim is to deduce some sharp Turán type inequalities for modified Bessel functions of the first and second kinds. Our proofs are based on explicit formulas for the Turánians of the modified Bessel functions of the first and second kinds and on a formula which is related to the infinite divisibility of the Student t-distribution. [ABSTRACT FROM AUTHOR]

Abstract: In this note our aim is to deduce some sufficient conditions for integral operators involving Bessel functions of the first kind to be univalent in the open unit disk. The key tools in our proofs are the generalized versions of the well-known Ahlfors’ and Becker’s univalence criteria and some inequalities for the normalized Bessel functions of the first kind. [Copyright &y& Elsevier]

Abstract: In this paper our aim is to show that if a probability density function is geometrically concave (convex), then the corresponding cumulative distribution function and the survival function are geometrically concave (convex) too, under some assumptions. The proofs are based on the so-called monotone form of l''Hospital''s rule and permit us to extend our results to the case of the concavity (convexity) with respect to Hölder means. To illustrate the applications of the main results, we discuss in details the geometrical concavity of the probability density function, cumulative distribution function and survival function of some common continuous univariate distributions. Moreover, at the end of the paper, we present a simple alternative proof to Schweizer''s problem related to the Mulholland''s generalization of Minkowski''s inequality. [Copyright &y& Elsevier]

In this paper, we study the generalized Marcum Q-function Qv(a,b), where a,v > 0 and b ≥ 0. Our aim is to extend the results of Corazza and Ferrari (IEEE Trans. Inf. Theory, vol. 48, pp. 3003-3008, 2002) to the generalized Marcum Q-function in order to deduce some new tight lower and upper bounds. The key tools in our proofs are some monotonicity properties of certain functions involving the modified Bessel function of the first kind and some classical inequalities, i.e., the Cauchy-Buniakowski-Schwarz and Chebyshev integral inequalities. These bounds are shown to be very tight for large b, i.e., the relative errors of our bounds converge to zero as b increases. Both theoretical analysis and numerical results are provided to show the tightness of our bounds. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we study the monotonicity properties of some functions involving the Mills'' ratio of the standard normal law. From these we deduce some new functional inequalities involving the Mills'' ratio, and we show that the Mills'' ratio is strictly completely monotonic. At the end of this paper we present some Turán-type inequalities for Mills'' ratio. [Copyright &y& Elsevier]

Abstract: The intrinsic properties, including logarithmic convexity (concavity), of the modified Bessel functions of the first kind and some other related functions are obtained. Several inequalities involving functions under discussion are established. [Copyright &y& Elsevier]

The article presents a study on trigonometric inequalities and its extension to Bessel functions. The aim of the study is to stretch some A. Oppenheim's inequalities to Bessel functions. The authors deduce the hyperbolic analogue of these trigonometric inequalities for the said extension. In 1958, Oppenheim and Carver provided a partial solution to Oppenheim's problems, while L. Zhu has recently solved the said problem completely. Also, Á Baricz extended the Carver solution to Bessel functions.

Abstract: Let be the generalized and normalized Bessel function depending on parameters and let , . Motivated by an open problem of Anderson, Vamanamurthy, and Vuorinen we prove that for all for certain conditions on the parameters . [Copyright &y& Elsevier]