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arXiv · 2602.18121

On Large Induced Outerplanar Subgraphs in $2$-Outerplanar Graphs

Marco D'Elia·Fabrizio Frati
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Abstract

Borradaile, Le and Sherman-Bennett [Graphs and Combinatorics, 2017] proved that every $n$-vertex $2$-outerplane graph has a set of at least $2n/3$ vertices that induces an outerplane graph. We identify a major flaw in their proof and recover their result with a different, and unfortunately much more complex, proof.

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Marco D'Elia, Fabrizio Frati. 2026-02-20. On Large Induced Outerplanar Subgraphs in $2$-Outerplanar Graphs. https://arxiv.org/abs/2602.18121

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