Results 11 to 20 of about 552 (213)
Graphs of low chordality [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 The chordality of a graph with at least one cycle is the length of the longest induced cycle in it. The odd (even) chordality is defined to be the length of the longest induced odd (even) cycle in it. Chordal graphs have chordality at most 3.
Sunil Chandran +2 more
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On chordal phylogeny graphs [PDF]
Discrete Applied Mathematics, 2021 An acyclic digraph each vertex of which has indegree at most $i$ and outdegree at most $j$ is called an $(i, j)$ digraph for some positive integers $i$ and $j$. Lee {\it et al.} (2017) studied the phylogeny graphs of $(2, 2)$ digraphs and gave sufficient conditions and necessary conditions for $(2, 2)$ digraphs having chordal phylogeny graphs.
Soogang Eoh, Suh-Ryung Kim
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Hyperbolicity and Chordality of a Graph [PDF]
The Electronic Journal of Combinatorics, 2011 Let $G$ be a connected graph with the usual shortest-path metric $d$. The graph $G$ is $\delta$-hyperbolic provided for any vertices $x,y,u,v$ in it, the two larger of the three sums $d(u,v)+d(x,y),d(u,x)+d(v,y)$ and $d(u,y)+d(v,x)$ differ by at most $2\delta.$ The graph $G$ is $k$-chordal provided it has no induced cycle of length greater than $k ...
Yaokun Wu, Chengpeng Zhang
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Branchwidth of chordal graphs [PDF]
Discrete Applied Mathematics, 2009 This paper revisits the ‘branchwidth territories' of Kloks, Kratochvíl and Müller [T. Kloks, J. Kratochvíl, H. Müller, New branchwidth territories, in: 16th Ann. Symp. on Theoretical Aspect of Computer Science, STACS, in: Lecture Notes in Computer Science, vol. 1563, 1999, pp.
Paul, Christophe, Telle, Jan Arne
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Semipaired Domination in Some Subclasses of Chordal Graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2021 A dominating set $D$ of a graph $G$ without isolated vertices is called semipaired dominating set if $D$ can be partitioned into $2$-element subsets such that the vertices in each set are at distance at most $2$. The semipaired domination number, denoted
Michael A. Henning +2 more
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Capturing Logarithmic Space and Polynomial Time on Chordal Claw-Free Graphs [PDF]
Logical Methods in Computer Science, 2019 We show that the class of chordal claw-free graphs admits LREC$_=$-definable canonization. LREC$_=$ is a logic that extends first-order logic with counting by an operator that allows it to formalize a limited form of recursion.
Berit Grußien
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A Short Proof of the Size of Edge-Extremal Chordal Graphs
Journal of Mathematical Sciences and Modelling, 2022 [3] have recently determined the maximum number of edges of a chordal graph with a maximum degree less than $d$ and the matching number at most $\nu$ by exhibiting a family of chordal graphs achieving this bound. We provide simple proof of their result.
Mordechai Shalom
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Decycling a graph by the removal of a matching: new algorithmic and structural aspects in some classes of graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2018 A graph $G$ is {\em matching-decyclable} if it has a matching $M$ such that $G-M$ is acyclic. Deciding whether $G$ is matching-decyclable is an NP-complete problem even if $G$ is 2-connected, planar, and subcubic.
Fábio Protti, Uéverton S. Souza
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Polynomial kernels for edge modification problems towards block and strictly chordal graphs [PDF]
Discrete Mathematics & Theoretical Computer ScienceWe consider edge modification problems towards block and strictly chordal graphs, where one is given an undirected graph $G = (V,E)$ and an integer $k \in \mathbb{N}$ and seeks to edit (add or delete) at most $k$ edges from $G$ to obtain a block graph or
Maël Dumas +3 more
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On the End-Vertex Problem of Graph Searches [PDF]
Discrete Mathematics & Theoretical Computer Science, 2019 End vertices of graph searches can exhibit strong structural properties and are crucial for many graph algorithms. The problem of deciding whether a given vertex of a graph is an end-vertex of a particular search was first introduced by Corneil, K\"ohler
Jesse Beisegel +6 more
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