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arXiv · 1708.05152

Triangle-Free Penny Graphs: Degeneracy, Choosability, and Edge Count

David Eppstein
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Abstract

We show that triangle-free penny graphs have degeneracy at most two, list coloring number (choosability) at most three, diameter $D=\Omega(\sqrt n)$, and at most $\min\bigl(2n-\Omega(\sqrt n),2n-D-2\bigr)$ edges.

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David Eppstein. 2017-08-17. Triangle-Free Penny Graphs: Degeneracy, Choosability, and Edge Count. https://doi.org/10.7155/jgaa.00463

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