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On solutions to q-difference equations for q-appell functions in the spirit of Olsson and Exton

  • Thomas Ernst EMAIL logo
Published/Copyright: June 9, 2025
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Abstract

The purpose of this article is to find many solutions of the canonical q-difference equations for q-Appell functions Φ2, Φ3, Φ4, starting with the first four ones, previously published. Furthermore, q-Laplace integral expressions for two of these functions in the form q-confluent functions are used to find more solutions. In order to explain the discrepancies between meromorphic continuations of multiple q-hypergeometric functions and q-analogues of analytic continuations of corresponding multiple hypergeometric functions, the notion pseudo-meromorphic continuation is introduced to denote equivalence classes of solutions of other q-analogues of systems of partial differential equations. To this end, we introduce equivalence classes of (systems of) partial q-difference equations. Some q-integrals for corresponding q-Appell functions and the second q-Horn function are also proved. In the process, we find a meromorphic continuation of the second q-Horn function. In some formulas, abbreviated notations are used together with combinatorial reasonings. Many proofs use formulas from our first book, which are quoted in detail.

  1. (Communicated by Giuseppe Di Fazio)

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Received: 2024-10-19
Accepted: 2025-01-02
Published Online: 2025-06-09
Published in Print: 2025-06-26

© 2025 Mathematical Institute Slovak Academy of Sciences

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