Results 21 to 30 of about 98 (93)
Treewidth and pathwidth of permutation graphs [PDF]
SIAM Journal on Discrete Mathematics, 1993 This paper is the first one in a series of articles using scanlines in intersection models of graphs. The new concept enables to prove that every minimal triangulation of a permutation graph into a chordal graph is an interval graph, a result that generalizes to minimal triangulations of asteroidal-triple free graphs [Discrete Appl. Math.
Bodlaender, H.L. +2 more
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Pathwidth and Nonrepetitive List Coloring
The Electronic Journal of Combinatorics, 2016 A vertex coloring of a graph is nonrepetitive if there is no path in the graph whose first half receives the same sequence of colors as the second half. While every tree can be nonrepetitively colored with a bounded number of colors (4 colors is enough), Fiorenzi, Ochem, Ossona de Mendez, and Zhu recently showed that this does not extend to the list ...
Gagol, Adam +3 more
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Approximation of pathwidth of outerplanar graphs [PDF]
Journal of Algorithms, 2001 Summary: There exists a polynomial time algorithm to compute the pathwidth of outerplanar graphs, but the large exponent makes this algorithm impractical. In this paper, we give an algorithm that, given a biconnected outerplanar graph \(G\), finds a path decomposition of \(G\) of pathwidth at most twice the pathwidth of \(G\) plus one.
Bodlaender, H.L., Fomin, F.V.
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Approximating Pathwidth for Graphs of Small Treewidth [PDF]
ACM Transactions on Algorithms, 2021 We describe a polynomial-time algorithm which, given a graphGwith treewidtht, approximates the pathwidth ofGto within a ratio of\(O(t\sqrt {\log t})\). This is the first algorithm to achieve anf(t)-approximation for some functionf.Our approach builds on the following key insight: every graph with large pathwidth has large treewidth or contains a ...
Carla Groenland +3 more
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Outerplanar Obstructions for Matroid Pathwidth
Electronic Notes in Discrete Mathematics, 2011 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Koutsonas, Athanassios +2 more
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The Pebble-Relation Comonad in Finite Model Theory [PDF]
Logical Methods in Computer ScienceThe pebbling comonad, introduced by Abramsky, Dawar and Wang, provides a categorical interpretation for the k-pebble games from finite model theory.
Yoàv Montacute, Nihil Shah
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Semantic Tree-Width and Path-Width of Conjunctive Regular Path Queries [PDF]
Logical Methods in Computer ScienceWe show that the problem of whether a query is equivalent to a query of tree-width $k$ is decidable, for the class of Unions of Conjunctive Regular Path Queries with two-way navigation (UC2RPQs).
Diego Figueira, Rémi Morvan
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Circumference and Pathwidth of Highly Connected Graphs [PDF]
Journal of Graph Theory, 2014 AbstractBirmele [J Graph Theory 2003] proved that every graph with circumference t has treewidth at most . Under the additional assumption of 2‐connectivity, such graphs have bounded pathwidth, which is a qualitatively stronger conclusion. Birmele's theorem was extended by Birmele et al.
Marshall, Emily A., Wood, David R.
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On first-order transductions of classes of graphs [PDF]
Logical Methods in Computer ScienceWe study various aspects of the first-order transduction quasi-order on graph classes, which provides a way of measuring the relative complexity of graph classes based on whether one can encode the other using a formula of first-order (FO) logic.
Samuel Braunfeld +3 more
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Discrete Mathematics & Theoretical Computer ScienceNot every directed acyclic graph (DAG) whose underlying undirected graph is planar admits an upward planar drawing. We are interested in pushing the notion of upward drawings beyond planarity by considering upward $k$-planar drawings of DAGs in which the
Patrizio Angelini +10 more
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