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arXiv · 0909.5278

Finding Induced Subgraphs via Minimal Triangulations

Fedor V. Fomin·Yngve Villanger
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Abstract

Potential maximal cliques and minimal separators are combinatorial objects which were introduced and studied in the realm of minimal triangulations problems including Minimum Fill-in and Treewidth. We discover unexpected applications of these notions to the field of moderate exponential algorithms. In particular, we show that given an n-vertex graph G together with its set of potential maximal cliques Pi_G, and an integer t, it is possible in time |Pi_G| * n^(O(t)) to find a maximum induced subgraph of treewidth t in G; and for a given graph F of treewidth t, to decide if G contains an induced subgraph isomorphic to F. Combined with an improved algorithm enumerating all potential maximal cliques in time O(1.734601^n), this yields that both problems are solvable in time 1.734601^n * n^(O(t)).

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Fedor V. Fomin, Yngve Villanger. 2009-12-22. Finding Induced Subgraphs via Minimal Triangulations. https://arxiv.org/abs/0909.5278

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