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arXiv · 1410.0309

10-Gabriel graphs are Hamiltonian

Tomáš Kaiser·Maria Saumell·Nico Van Cleemput
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Abstract

Given a set $S$ of points in the plane, the $k$-Gabriel graph of $S$ is the geometric graph with vertex set $S$, where $p_i,p_j\in S$ are connected by an edge if and only if the closed disk having segment $\bar{p_ip_j}$ as diameter contains at most $k$ points of $S \setminus \{p_i,p_j\}$. We consider the following question: What is the minimum value of $k$ such that the $k$-Gabriel graph of every point set $S$ contains a Hamiltonian cycle? For this value, we give an upper bound of 10 and a lower bound of 2. The best previously known values were 15 and 1, respectively.

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Tomáš Kaiser, Maria Saumell, Nico Van Cleemput. 2015-06-06. 10-Gabriel graphs are Hamiltonian. https://arxiv.org/abs/1410.0309

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