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On Ramanujan’s inverse digamma approximation

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Abstract

In this paper, we consider an asymptotic series for the inverse of the Digamma function given by Ramanujan. We derive formulas for the computation of the coefficients of this asymptotic series, and describe their asymptotic behaviour as well.

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Acknowledgments

I am most grateful to the Almighty God for his mercies and guidance throughout this research. I am thankful to Gergő Nemes for suggesting this problem to me and for his thorough, constructive and helpful comments and suggestions on the manuscript. I would also like to thank the anonymous referee for his/her helpful comments and suggestions on the manuscript. Finally I would also like to thank all my friends and family members especially my parent Mr and Mrs Issaka for their loving support and sacrifices.

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Authors and Affiliations

  1. Department of Mathematics and its Applications, Central European University, Nádor utca 9, Budapest, 1051, Hungary

    Aziz Issaka

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  1. Aziz Issaka
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Correspondence to Aziz Issaka.

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Issaka, A. On Ramanujan’s inverse digamma approximation. Ramanujan J 39, 291–302 (2016). https://doi.org/10.1007/s11139-014-9659-3

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  • DOI: https://doi.org/10.1007/s11139-014-9659-3

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