Exponential starlikeness and convexity of confluent hypergeometric, Lommel and Struve functions

Adiba Naz; Sumit Nagpal; V. Ravichandran

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arXiv · 1908.07266

Exponential starlikeness and convexity of confluent hypergeometric, Lommel and Struve functions

Adiba Naz·Sumit Nagpal·V. Ravichandran

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Abstract

Sufficient conditions are obtained on the parameters of Lommel function of the first kind, generalized Struve function of the first kind and the confluent hypergeometric function under which these special functions become exponential convex and exponential starlike in the open unit disk. The method of differential subordination is employed in proving the results. Few examples are also provided to illustrate the results obtained.

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Adiba Naz, Sumit Nagpal, V. Ravichandran. 2019-08-20. Exponential starlikeness and convexity of confluent hypergeometric, Lommel and Struve functions. https://arxiv.org/abs/1908.07266

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