Results 31 to 40 of about 1,168 (127)
Characterizing and computing minimal cograph completions [PDF]
Discrete Applied Mathematics, 2008 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Papadopoulos, C. +2 more
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$2$-polarity and algorithmic aspects of polarity variants on cograph superclasses [PDF]
Discrete Mathematics & Theoretical Computer ScienceA graph $G$ is said to be an $(s, k)$-polar graph if its vertex set admits a partition $(A, B)$ such that $A$ and $B$ induce, respectively, a complete $s$-partite graph and the disjoint union of at most $k$ complete graphs.
Fernando Esteban Contreras-Mendoza +1 more
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Partitions of Graphs into Cographs
Electronic Notes in Discrete Mathematics, 2002 A cograph is a graph that can be constructed by a single vertex using complementation and disjoint union operations. Equivalently, cographs are exactly those graphs which do not contain an induced path \(P_4\) with four vertices and three edges. The \(c\)-chromatic number \(c(G)\) of a graph \(G\) is the minimum number \(k\) such that the vertex set of
Gimbel, John, Nešetřil, Jaroslav
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Defining and identifying cograph communities in complex networks
New Journal of Physics, 2015 Community or module detection is a fundamental problem in complex networks. Most of the traditional algorithms available focus only on vertices in a subgraph that are densely connected among themselves while being loosely connected to the vertices ...
Songwei Jia +6 more
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Cograph Regularized Collective Nonnegative Matrix Factorization for Multilabel Image Annotation
IEEE Access, 2019 Automatic image annotation is an effective and straightforward way to facilitate many applications in computer vision. However, manually annotating images is a computation-expensive and labor-intensive task. To address these problems, this paper proposes
Juli Zhang +3 more
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Characterizing –partitionable Cographs
Electronic Notes in Discrete Mathematics, 2005 Abstract We consider the problem of partitioning a graph into k independent sets and l cliques, known as the ( k , l ) -partition problem, which was introduced by Brandstadt in [A. Bransdstadt, Partitions of graphs into one or two independent sets and cliques, Discrete Mathematics 152 (1996) 47–54], and generalized by Feder et al.
Raquel de Souza Francisco +2 more
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On Certain Eigenspaces of Cographs [PDF]
The Electronic Journal of Combinatorics, 2008 For every cograph there exist bases of the eigenspaces for the eigenvalues $0$ and $-1$ that consist only of vectors with entries from $\{0, 1, -1\}$, a property also exhibited by other graph classes. Moreover, the multiplicities of the eigenvalues $0$ and $-1$ of a cograph can be determined by counting certain vertices of the associated cotree.
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Algorithmic aspects of switch cographs
Discrete Applied Mathematics, 2016 This paper introduces the notion of involution module, the first generalization of the modular decomposition of 2-structure which has a unique linear-sized decomposition tree. We derive an O(n^2) decomposition algorithm and we take advantage of the involution modular decomposition tree to state several algorithmic results.
Cohen-Addad, Vincent +2 more
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A Diagonalization Algorithm for the Distance Matrix of Cographs
IEEE Access, 2018 Cographs is a well-known class of graphs in graph theory, which can be generated from a single vertex by applying a series of complement (or equivalently join operations) and disjoint union operations.
Zhibin Du
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, 2010 Many fixed-parameter tractable algorithms using a bounded search tree have been repeatedly improved, often by describing a larger number of branching rules involving an increasingly complex case analysis.
A. Cournier +17 more
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