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arXiv · 1012.2470

The zero-divisor graphs of semirings

David Dolžan·Polona Oblak
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Abstract

In this paper we study zero--divisor graphs of rings and semirings. We show that all zero--divisor graphs of (possibly noncommutative) semirings are connected and have diameter less than or equal to 3. We characterize all acyclic zero-divisor graphs of semirings and prove that in the case zero-divisor graphs are cyclic, their girths are less than or equal to 4. We find all possible cyclic zero-divisor graphs over commutative semirings having at most one 3-cycle, and characterize all complete $k$-partite and regular zero-divisor graphs. Moreover, we characterize all additively cancellative commutative semirings and all commutative rings such that their zero--divisor graph has exactly one 3-cycle.

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David Dolžan, Polona Oblak. 2010-12-11. The zero-divisor graphs of semirings. https://arxiv.org/abs/1012.2470

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