Results 21 to 30 of about 1,168 (127)
Signed graphs with integral net Laplacian spectrum
AKCE International Journal of Graphs and Combinatorics, 2023 Given a signed graph [Formula: see text], let [Formula: see text] and [Formula: see text] be its standard adjacency matrix and the diagonal matrix of net-degrees, respectively.
M. Anđelić +3 more
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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
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Finite groups whose coprime graph is split, threshold, chordal, or a cograph [PDF]
Proceedings of the Estonian Academy of SciencesGiven a finite group G, the coprime graph of G, denoted by Î(G), is defined as an undirected graph with the vertex set G, and for distinct x, y â G, x is adjacent to y if and only if (o(x), o(y)) = 1, where o(x) and o(y) are the orders of x and y ...
Jin Chen, Shixun Lin, Xuanlong Ma
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When Is a Graded Free Complex Exact?
Mathematics, 2022 Minimal free resolutions of a finitely generated module over a polynomial ring S=k[x], with variables x={x1,…,xn} and a field k have been extensively studied.
David C. Molano +2 more
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Removing Twins in Graphs to Break Symmetries
Mathematics, 2019 Determining vertex subsets are known tools to provide information about automorphism groups of graphs and, consequently about symmetries of graphs. In this paper, we provide both lower and upper bounds of the minimum size of such vertex subsets, called ...
Antonio González, María Luz Puertas
doaj +1 more source
Independent Set Reconfiguration in Cographs [PDF]
, 2014 We study the following independent set reconfiguration problem, called TAR-Reachability: given two independent sets $I$ and $J$ of a graph $G$, both of size at least $k$, is it possible to transform $I$ into $J$ by adding and removing vertices one-by-one,
AE Mouawad +21 more
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Discrete Applied Mathematics, 2007 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Ekim, T., Mahadev, N.V.R., de Werra, D.
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Characterization of Graphs with an Eigenvalue of Large Multiplicity
Advances in Mathematical Physics, Volume 2020, Issue 1, 2020., 2020 Let G be a simple and undirected graph. The eigenvalues of the adjacency matrix of G are called the eigenvalues of G. In this paper, we characterize all the n‐vertex graphs with some eigenvalue of multiplicity n − 2 and n − 3, respectively. Moreover, as an application of the main result, we present a family of nonregular graphs with four distinct ...
Linming Qi +4 more
wiley +1 more source
Cographs: Eigenvalues and Dilworth number [PDF]
Discrete Mathematics, 2019 13 pages, Comments from referees ...
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On perfect and quasiperfect dominations in graphs [PDF]
, 2017 A subset S ¿ V in a graph G = ( V , E ) is a k -quasiperfect dominating set (for k = 1) if every vertex not in S is adjacent to at least one and at most k vertices in S .
Cáceres, José +4 more
core +2 more sources