Results 1 to 10 of about 1,423 (126)
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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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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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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P_4-Colorings and P_4-Bipartite Graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2001 A vertex partition of a graph into disjoint subsets V_is is said to be a P_4-free coloring if each color class V_i induces a subgraph without chordless path on four vertices (denoted by P_4).
Chinh T. Hoàng, Van Bang Le
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Capturing Polynomial Time using Modular Decomposition [PDF]
Logical Methods in Computer Science, 2019 The question of whether there is a logic that captures polynomial time is one of the main open problems in descriptive complexity theory and database theory.
Berit Grußien
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Families of Integral Cographs within a Triangular Array
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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Sum structures in abelian groups
Examples and Counterexamples, 2023 Any set S of elements from an abelian group produces a graph with colored edges G(S), with its points the elements of S, and the edge between points P and Q assigned for its “color” the sum P+Q.
Robert Haas
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Partial Homology Relations - Satisfiability in terms of Di-Cographs [PDF]
, 2018 Directed cographs (di-cographs) play a crucial role in the reconstruction of evolutionary histories of genes based on homology relations which are binary relations between genes.
A Brandstädt +32 more
core +2 more sources