Uniformly convergent expansions for the generalized hypergeometric functions p –1Fp and pFp

We derive a convergent expansion of the generalized hypergeometric function p−1 F p in terms of the Bessel functions 0 F 1 that holds uniformly with respect to the argument in any horizontal strip of the complex plane. We further obtain a convergent expansion of the generalized hypergeometric functi...

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Bibliographic Details
Authors: López García, José Luis, Pagola Martínez, Pedro Jesús, Karp, D. B.
Format: article
Status:Versión aceptada para publicación
Publication Date:2020
Country:España
Institution:Universidad Pública de Navarra
Repository:Academica-e. Repositorio Institucional de la Universidad Pública de Navarra
OAI Identifier:oai:academica-e.unavarra.es:2454/37317
Online Access:https://hdl.handle.net/2454/37317
Access Level:Open access
Keyword:Generalized hypergeometric function
Bessel function
Kummer function
Convergent expansions
Uniform expansions
Description
Summary:We derive a convergent expansion of the generalized hypergeometric function p−1 F p in terms of the Bessel functions 0 F 1 that holds uniformly with respect to the argument in any horizontal strip of the complex plane. We further obtain a convergent expansion of the generalized hypergeometric function p F p in terms of the confluent hypergeometric functions 1 F 1 that holds uniformly in any right half-plane. For both functions, we make a further step forward and give convergent expansions in terms of trigonometric, exponential and rational functions that hold uniformly in the same domains. For all four expansions we present explicit error bounds. The accuracy of the approximations is illustrated by some numerical experiments.