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arXiv · 1511.05020

The Kelmans-Seymour conjecture I: special separations

Dawei He·Yan Wang·Xingxing Yu
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Abstract

Seymour and, independently, Kelmans conjectured in the 1970s that every 5-connected nonplanar graph contains a subdivision of $K_5$. This conjecture was proved by Ma and Yu for graphs containing $K_4^-$, and an important step in their proof is to deal with a 5-separation in the graph with a planar side. In order to establish the Kelmans-Seymour conjecture for all graphs, we need to consider 5-separations and 6-separations with less restrictive structures. The goal of this paper is to deal with special 5-separations and 6-separations, including those with an apex side. Results will be used in subsequent papers to prove the Kelmans-Seymour conjecture.

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Dawei He, Yan Wang, Xingxing Yu. 2015-11-16. The Kelmans-Seymour conjecture I: special separations. https://arxiv.org/abs/1511.05020

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