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

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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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Authors and Affiliations

  1. Department of Mathematics, University of Delhi, Delhi, 110 007, India

    Adiba Naz

  2. Department of Mathematics, Ramanujan College, University of Delhi, Delhi, 110 019, India

    Sumit Nagpal

  3. Department of Mathematics, National Institute of Technology, Tiruchirappalli, 620 015, India

    V. Ravichandran

Authors
  1. Adiba Naz
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  2. Sumit Nagpal
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  3. V. Ravichandran
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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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  • DOI: https://doi.org/10.1007/s00009-020-01621-4

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