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arXiv · 1606.05271

A Carlitz-von Staudt type theorem for finite rings

Apoorva Khare·Akaki Tikaradze
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Abstract

We compute the $k$th power-sums (for all $k>0$) over an arbitrary finite unital ring $R$. This unifies and extends the work of Brawley, Carlitz, and Levine for matrix rings [Duke Math. J. 1974], with folklore results for finite fields and finite cyclic groups, and more general recent results of Grau and Oller-Marcen for commutative rings [Finite Fields Appl. 2017]. As an application, we resolve a conjecture by Fortuny Ayuso, Grau, Oller-Marcen, and Rua on zeta values for matrix rings over finite commutative rings [Internat. J. Algebra Comput. 2017]. We further recast our main result via zeta values over polynomial rings, and end by classifying the translation-invariant polynomials over a large class of finite commutative rings.

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Apoorva Khare, Akaki Tikaradze. 2016-06-16. A Carlitz-von Staudt type theorem for finite rings. https://doi.org/10.1016/j.laa.2018.05.035

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