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arXiv · 1501.05046

Vertex-primitive digraphs having vertices with almost equal neighbourhoods

Pablo Spiga·Gabriel Verret
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Abstract

We consider vertex-primitive digraphs having two vertices with almost equal neighbourhoods (that is, the set of vertices that are neighbours of one but not the other is small). We prove a structural result about such digraphs and then apply it to answer a question of Araújo and Cameron about synchronising groups.

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Pablo Spiga, Gabriel Verret. 2015-01-21. Vertex-primitive digraphs having vertices with almost equal neighbourhoods. https://arxiv.org/abs/1501.05046

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