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arXiv · 1610.04407

A zero-sum problem on graphs

Daniel Weißauer
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Abstract

Call a graph $G$ zero-forcing for a finite abelian group $\mathcal{G}$ if for every $\ell : V(G) \to \mathcal{G}$ there is a connected $A \subseteq V(G)$ with $\sum_{a \in A} \ell(a) = 0$. The problem we pose here is to characterise the class of zero-forcing graphs. It is shown that a connected graph is zero-forcing for the cyclic group of prime order $p$ if and only if it has at least $p$ vertices. When $|\mathcal{G}|$ is not prime, however, being zero-forcing is intimately linked to the structure of the graph. We obtain partial solutions for the general case, discuss computational issues and present several questions.

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Daniel Weißauer. 2016-10-14. A zero-sum problem on graphs. https://arxiv.org/abs/1610.04407

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