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Functional equations for exponential polynomials


The aim of the present paper is to describe some properties of functions with finite dimensional difference spaces by means of spectral analysis and spectral synthesis. We are going to apply these results to a version of a Levi-Civita functional equation, which has been recently studied by J. M. Almira and E. Shulman.


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László Székelyhidi was partly supported by the Hungarian National Foundation for Scientific Research (OTKA), Grant No. K111651, and by BIUST, Botswana. Żywilla Fechner was supported by the National Science Centre, Poland, Grant No. DEC-2017/01/X/ST1/00916.

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Correspondence to Żywilla Fechner.

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Fechner, Ż., Székelyhidi, L. Functional equations for exponential polynomials. Aequat. Math. 93, 535–545 (2019).

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Mathematics Subject Classification

  • 39B99
  • 43A62
  • 20N20


  • Exponential polynomials
  • Levi-Civita equation
  • Hypergroups