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arXiv · 2203.13233

Grid Induced Minor Theorem for Graphs of Small Degree

Tuukka Korhonen
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Abstract

A graph $H$ is an induced minor of a graph $G$ if $H$ can be obtained from $G$ by vertex deletions and edge contractions. We show that there is a function $f(k, d) = O(k^{10} + 2^{d^5})$ so that if a graph has treewidth at least $f(k, d)$ and maximum degree at most $d$, then it contains a $k \times k$-grid as an induced minor. This proves the conjecture of Aboulker, Adler, Kim, Sintiari, and Trotignon [Eur. J. Comb., 98, 2021] that any graph with large treewidth and bounded maximum degree contains a large wall or the line graph of a large wall as an induced subgraph. It also implies that for any fixed planar graph $H$, there is a subexponential time algorithm for maximum weight independent set on $H$-induced-minor-free graphs.

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Tuukka Korhonen. 2022-03-24. Grid Induced Minor Theorem for Graphs of Small Degree. https://doi.org/10.1016/j.jctb.2023.01.002

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