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The Tree Stabbing Number is not Monotone

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 نشر من قبل Johannes Obenaus
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
والبحث باللغة English




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Let $P subseteq mathbb{R}^2$ be a set of points and $T$ be a spanning tree of $P$. The emph{stabbing number} of $T$ is the maximum number of intersections any line in the plane determines with the edges of $T$. The emph{tree stabbing number} of $P$ is the minimum stabbing number of any spanning tree of $P$. We prove that the tree stabbing number is not a monotone parameter, i.e., there exist point sets $P subsetneq P$ such that treestab{$P$} $>$ treestab{$P$}, answering a question by Eppstein cite[Open Problem~17.5]{eppstein_2018}.

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