Results 31 to 40 of about 2,587 (156)
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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Pagenumber of pathwidth-k graphs and strong pathwidth-k graphs
Discrete Mathematics, 2002 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Togasaki, Mitsunori, Yamazaki, Koichi
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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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The Firefighter Problem: A Structural Analysis [PDF]
, 2014 We consider the complexity of the firefighter problem where b>=1 firefighters are available at each time step. This problem is proved NP-complete even on trees of degree at most three and budget one (Finbow et al.,2007) and on trees of bounded degree b+3
A King +16 more
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Solving Vertex Cover in Polynomial Time on Hyperbolic Random Graphs [PDF]
, 2020 The VertexCover problem is proven to be computationally hard in different ways: It is NP-complete to find an optimal solution and even NP-hard to find an approximation with reasonable factors.
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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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Majority constraints have bounded pathwidth duality
European Journal of Combinatorics, 2008 This work was partially supported by the UK EPSRC grant EP/C54384X/1. Part of this work was done when both authors visited the Isaac Newton Institute for Mathematical Sciences, Cambridge. The financial support provided by the Institute is gratefully acknowledged.
Víctor Dalmau, Andrei Krokhin
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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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