Normality criteria for families of meromorphic functions

Abstract

In this paper we prove some normality criteria for a family of meromorphic functions, which involves the zeros of certain differential polynomials generated by the members of the family.

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Acknowledgement

The second author is thankful to the faculty and the administrative unit of School of Mathematics, Harish-Chandra Research Institute, Allahabad for their warm hospitality during the preparation of this paper.

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Correspondence to Sanjay Kumar or Poonam Rani.

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The research work of the second author is supported by research fellowship from CSIR India

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Kumar, S., Rani, P. Normality criteria for families of meromorphic functions. Indian J Pure Appl Math 51, 579–588 (2020). https://doi.org/10.1007/s13226-020-0418-4

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Key words

  • Meromorphic functions
  • holomorphic functions
  • normal families
  • Zalcman’s lemma

2010 Mathematics Subject Classification

  • 30D45
  • 30D35