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MONOTONICITY PROPERTIES OF THE GENERALIZED STRUVE FUNCTIONS

  • Ali, Rosihan M. (School of Mathematical Sciences Universiti Sains Malaysia) ;
  • Mondal, Saiful R. (Department of Mathematics and Statistics Collage of Science King Faisal University) ;
  • Nisar, Kottakkaran S. (Department of Mathematics College of Arts and Science Prince Sattam bin Abdulaziz University)
  • Received : 2016.03.01
  • Published : 2017.03.01

Abstract

This paper introduces and studies a generalization of the classical Struve function of order p given by $$_aS_{p,c}(x):=\sum\limits_{k=0}^{\infty}\frac{(-c)^k}{{\Gamma}(ak+p+\frac{3}{2}){\Gamma}(k+\frac{3}{2})}(\frac{x}{2})^{2k+p+1}$$. Representation formulae are derived for $_aS_{p,c}$. Further the function $_aS_{p,c}$ is shown to be a solution of an (a + 1)-order differential equation. Monotonicity and log-convexity properties for the generalized Struve function $_aS_{p,c}$ are investigated, particulary for the case c = -1. As a consequence, $Tur{\acute{a}}n$-type inequalities are established. For a = 2 and c = -1, dominant and subordinant functions are obtained for the Struve function $_2S_{p,-1}$.

Keywords

Acknowledgement

Supported by : FRGS

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