Results 1 to 10 of about 412 (107)
Orthology and near-cographs in the context of phylogenetic networks [PDF]
Algorithms for Molecular BiologyOrthologous genes, which arise through speciation, play a key role in comparative genomics and functional inference. In particular, graph-based methods allow for the inference of orthology estimates without prior knowledge of the underlying gene or ...
Anna Lindeberg +3 more
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Relative timing information and orthology in evolutionary scenarios [PDF]
Algorithms for Molecular Biology, 2023 Background Evolutionary scenarios describing the evolution of a family of genes within a collection of species comprise the mapping of the vertices of a gene tree T to vertices and edges of a species tree S.
David Schaller +5 more
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Defining and identifying cograph communities in complex networks [PDF]
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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Families of Integral Cographs within a Triangular Array [PDF]
Special Matrices, 2020 The determinant Hosoya triangle, is a triangular array where the entries are the determinants of two-by-two Fibonacci matrices. The determinant Hosoya triangle mod 2 gives rise to three infinite families of graphs, that are formed by complete product ...
Ching Hsin-Yun +2 more
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Cograph Regularized Collective Nonnegative Matrix Factorization for Multilabel Image Annotation [PDF]
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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Sombor characteristic values of cographs [PDF]
HeliyonA unique class of cograph is examined, that is defined recursively as C=C(n1)=K‾n1, and C=C(n1,n2,…,ni)=C(n1,n2,…,ni−1)∪Kni‾, for 2≤i≤k. The Sombor spectrum of C is calculated, the Sombor spectral radius and establish the sharp bounds for the Sombor ...
Zahid Raza +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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Theory and Applications of GraphsA class G of graphs is called hereditary if it is closed under taking induced subgraphs. We denote by G^{apex} the class of graphs G that contain a vertex v such that G − v is in G.
Jagdeep Singh +2 more
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Forbidden subgraphs in reduced power graphs of finite groups
AIMS Mathematics, 2021 Let G be a finite group. The reduced power graph of G is the undirected graph whose vertex set consists of all elements of G, and two distinct vertices x and y are adjacent if either ⟨x⟩⊂⟨y⟩ or ⟨y⟩⊂⟨x⟩. In this paper, we show that the reduced power graph
Huani Li , Ruiqin Fu, Xuanlong Ma
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An Analytic Propositional Proof System on Graphs [PDF]
Logical Methods in Computer Science, 2022 In this paper we present a proof system that operates on graphs instead of formulas. Starting from the well-known relationship between formulas and cographs, we drop the cograph-conditions and look at arbitrary undirected) graphs. This means that we lose
Matteo Acclavio +2 more
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