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arXiv · 2105.11633

Minimal graph in which the intersection of two longest paths is not a separator

Juan Gutiérrez·Christian Valqui
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Abstract

We prove that for a connected simple graph $G$ with $n\le 10$ vertices, and two longest paths $C$ and $D$ in $G$, the intersection of vertex sets $V(C)\cap V(D)$ is a separator. This shows that the graph found previously with $n=11$, in which the complement of the intersection of vertex sets $V(C)\cap V(D)$ of two longest paths is connected, is minimal.

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Juan Gutiérrez, Christian Valqui. 2021-05-25. Minimal graph in which the intersection of two longest paths is not a separator. https://arxiv.org/abs/2105.11633

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