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Wilson’s type Hilbert space valued functional equations

  • Driss Zeglami EMAIL logo , Mohamed Tial und Brahim Fadli
Veröffentlicht/Copyright: 12. Mai 2016
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Abstract

In the present paper we characterize, in terms of characters, additive functions and matrix elements of irreducible two-dimensional representations, the continuous solutions of some trigonometric functional equations for mappings defined on an arbitrary group and taking their values in a complex Hilbert space with the Hadamard product. In addition, we investigate a superstability result for these equations.

The authors would like to express their most sincere gratitude to the referee for a number of constructive comments which have led to an essential improvement of the paper.

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Received: 2016-2-15
Revised: 2016-4-4
Accepted: 2016-4-9
Published Online: 2016-5-12
Published in Print: 2016-7-1

© 2016 by De Gruyter

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