Abstract
We provide a unifying framework for the treatment of equations of the form
for additive maps f k and integers p k , q k (1 ≤ k ≤ n). We show how to solve many equations of this type, and we present some open problems. In general our unknown functions map an integral domain of characteristic zero into itself. When negative exponents appear, we restrict our attention to fields of characteristic zero. All of the results could be formulated for integral domains or fields of sufficiently large characteristic as well.
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Ebanks, B. Characterizing ring derivations of all orders via functional equations: results and open problems. Aequat. Math. 89, 685–718 (2015). https://doi.org/10.1007/s00010-014-0256-8
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DOI: https://doi.org/10.1007/s00010-014-0256-8