Exponential Starlikeness and Convexity of Confluent Hypergeometric, Lommel, and Struve Functions


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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Correspondence to Sumit Nagpal.

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Naz, A., Nagpal, S. & Ravichandran, V. Exponential Starlikeness and Convexity of Confluent Hypergeometric, Lommel, and Struve Functions. Mediterr. J. Math. 17, 204 (2020). https://doi.org/10.1007/s00009-020-01621-4

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  • Differential subordination
  • exponential function
  • Struve function
  • Lommel function
  • confluent hypergeometric function

Mathematics Subject Classification

  • Primary 30C45
  • Secondary 30C80