Existence of Erd\H{o}s-Burgess constant in commutative rings

Guoqing Wang

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arXiv · 2005.08955

Existence of Erd\H{o}s-Burgess constant in commutative rings

Guoqing Wang

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Abstract

Let $R$ be a commutative unitary ring. An idempotent in $R$ is an element $e\in R$ with $e^2=e$. The Erd\H{o}s-Burgess constant associated with the ring $R$ is the smallest positive integer $\ell$ (if exists) such that for any given $\ell$ elements (not necessarily distinct) of $R$, say $a_1,\ldots,a_{\ell}\in R$, there must exist a nonempty subset $J\subset \{1,2,\ldots,\ell\}$ with $\prod\limits_{j\in J} a_j$ being an idempotent. In this paper, we prove that except for an infinite commutative ring with a very special form, the Erd\H{o}s-Burgess constant of the ring $R$ exists if and only if $R$ is finite.

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Guoqing Wang. 2020-05-17. Existence of Erd\H{o}s-Burgess constant in commutative rings. https://arxiv.org/abs/2005.08955

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