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arXiv · 2101.05322

Characterizing extremal graphs for open neighbourhood location-domination

Florent Foucaud·Narges Ghareghani·Aida Roshany-Tabrizi·Pouyeh Sharifani
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Abstract

An open neighbourhood locating-dominating set is a set $S$ of vertices of a graph $G$ such that each vertex of $G$ has a neighbour in $S$, and for any two vertices $u,v$ of $G$, there is at least one vertex in $S$ that is a neighbour of exactly one of $u$ and $v$. We characterize those graphs whose only open neighbourhood locating-dominating set is the whole set of vertices. More precisely, we prove that these graphs are exactly the graphs all whose connected components are half-graphs (a half-graph is a special bipartite graph with both parts of the same size, where each part can be ordered so that the open neighbourhoods of consecutive vertices differ by exactly one vertex). This corrects a wrong characterization from the literature.

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Florent Foucaud, Narges Ghareghani, Aida Roshany-Tabrizi, Pouyeh Sharifani. 2021-01-13. Characterizing extremal graphs for open neighbourhood location-domination. https://doi.org/10.1016/j.dam.2021.06.006

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