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arXiv · 2412.14836

Sparse induced subgraphs in $P_7$-free graphs of bounded clique number

Maria Chudnovsky·Jadwiga Czyżewska·Kacper Kluk·Marcin Pilipczuk·Paweł Rzążewski
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Abstract

Many natural computational problems, including e.g. Max Weight Independent Set, Feedback Vertex Set, or Vertex Planarization, can be unified under an umbrella of finding the largest sparse induced subgraph, that satisfies some property definable in CMSO$_2$ logic. It is believed that each problem expressible with this formalism can be solved in polynomial time in graphs that exclude a fixed path as an induced subgraph. This belief is supported by the existence of a quasipolynomial-time algorithm by Gartland, Lokshtanov, Pilipczuk, Pilipczuk, and Rz\k{a}\.zewski [STOC 2021], and a recent polynomial-time algorithm for $P_6$-free graphs by Chudnovsky, McCarty, Pilipczuk, Pilipczuk, and Rz\k{a}\.zewski [SODA 2024]. In this work we extend polynomial-time tractability of all such problems to $P_7$-free graphs of bounded clique number.

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Maria Chudnovsky, Jadwiga Czyżewska, Kacper Kluk, Marcin Pilipczuk, Paweł Rzążewski. 2024-12-19. Sparse induced subgraphs in $P_7$-free graphs of bounded clique number. https://arxiv.org/abs/2412.14836

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