A generalization of Drygas functional equation


  • A. Charifi Ibn Tofail University.
  • Muaadh Almahalebi Ibn Tofail University.
  • Samir Kabbaj Ibn Tofail University.




Automorphism group, difference operator, Drygas functional equation, automorfismo de grupos, operador diferencial, ecuación funcional de Drygas.


We obtain the Solutions of the following Drygas functional equation

∑ λ ∈Φ f (x + λy + aλ ) = κf(x)+ ∑ λ ∈Φ f(λy), x, y ∈ S

where S is an abelian semigroup, G is an abelian group, f ∈ GS, Φ is a finite automorphism group of S with order k, and aλ ∈ S, λ∈Φ.

Author Biographies

A. Charifi, Ibn Tofail University.

Department of Mathematics, Faculty of Sciences.

Muaadh Almahalebi, Ibn Tofail University.

Department of Mathematics, Faculty of Sciences.

Samir Kabbaj, Ibn Tofail University.

Department of Mathematics, Faculty of Sciences.


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How to Cite

A. Charifi, M. Almahalebi, and S. Kabbaj, “A generalization of Drygas functional equation”, Proyecciones (Antofagasta, On line), vol. 35, no. 2, pp. 159-176, Mar. 2017.




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