Abstract
Let R be a finite commutative ring with identity. In this paper, given an integer \(k\ge 2\), we obtain an exact formula for the number of ways to represent each element of R as the sum of k exceptional units. This generalizes a recent result of Quan-Hui Yang and Qing-Qing Zhao for the case where R is the ring \({\mathbb {Z}}_n\) of residue classes modulo n.
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The author expresses his gratitude to the anonymous reviewer for his/her helpful comments and suggestions, which have improved the paper.
This work was supported by FCT project UID/EEA/50008/2013.
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Communicated by A. Constantin.
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Miguel, C. On the sumsets of exceptional units in a finite commutative ring. Monatsh Math 186, 315–320 (2018). https://doi.org/10.1007/s00605-017-1070-x
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DOI: https://doi.org/10.1007/s00605-017-1070-x