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Quadratic functions satisfying an additional equation

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Abstract

There is a result, due independently to Kurepa [14] and to Jurkat [12], which distinguishes linear functions or derivations from other additive functions as solutions to certain functional equations. The purpose of this paper is to prove an analogue of a part of this result, corresponding to derivations, for quadratic functions.

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Acknowledgement

The author would like to thank the anonymous referee for the careful reading of the manuscript and the valuable comments.

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  1. Division of Pure and Applied Science, Graduate School of Science and Technology, Gunma University, Tenjin-cho 1-5-1, Kiryu, 376-8515, Japan

    M. Amou

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  1. M. Amou
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Amou, M. Quadratic functions satisfying an additional equation. Acta Math. Hungar. 162, 40–51 (2020). https://doi.org/10.1007/s10474-020-01047-0

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  • DOI: https://doi.org/10.1007/s10474-020-01047-0

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