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arXiv · 2203.10239

Plane Triangulations Without Spanning 2-Trees

Allan Bickle
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Abstract

A 2-tree is a graph that can be formed by starting with a triangle and iterating the operation of making a new vertex adjacent to two adjacent vertices of the existing graph. Leizhen Cai asked in 1995 whether every maximal planar graph contains a spanning 2-tree. We answer this question in the negative by constructing an infinite class of maximal planar graphs that have no spanning 2-tree.

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Allan Bickle. 2022-03-19. Plane Triangulations Without Spanning 2-Trees. https://arxiv.org/abs/2203.10239

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