Abstract
In this paper, we study single variable functional equations that involve one unknown function and a finite set of known functions that form a group under the operation of composition. The main theorems give sufficient conditions for the existence and uniqueness of a (local) solution and also stability-type result for the solution. In the proofs, besides the standard methods of classical analysis, some group theoretical tools play a key role.
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Dedicated to the 60th birthday of Professor László Székelyhidi
This research has been supported by the Hungarian Scientific Research Fund (OTKA) Grants NK-81402.
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Bessenyei, M., Kézi, C.G. Solving functional equations via finite substitutions. Aequat. Math. 85, 593–600 (2013). https://doi.org/10.1007/s00010-012-0176-4
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DOI: https://doi.org/10.1007/s00010-012-0176-4