Results 81 to 90 of about 312 (179)
Stability for large forbidden subgraphs [PDF]
Journal of Graph Theory, 2009 AbstractIn this note we strengthen the stability theorem of Erdős and Simonovits. Write Kr(s1, …, sr) for the complete r‐partite graph with classes of sizes s1, …, sr and Tr(n) for the r‐partite Turán graph of order n. Our main result is:For all r≥2 and all sufficiently small c>0, ε>0, every graph G of sufficiently large order n with e(G)>(1−1/
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On Hereditary Helly classes of graphs
Discrete Mathematics & Theoretical Computer Science, 2008 In graph theory, the Helly property has been applied to families of sets, such as cliques, disks, bicliques, and neighbourhoods, leading to the classes of clique-Helly, disk-Helly, biclique-Helly, neighbourhood-Helly graphs, respectively.
Marina Groshaus, Jayme Luiz Szwarcfiter
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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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Small clique number graphs with three trivial critical ideals
Special Matrices, 2018 The critical ideals of a graph are the determinantal ideals of the generalized Laplacian matrix associated to a graph. Previously, they have been used in the understanding and characterizing of the graphs with critical group with few invariant factors ...
Alfaro Carlos A., Valencia Carlos E.
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The spectral Turán problem about graphs of given size with forbidden subgraphs
AKCE International Journal of Graphs and CombinatoricsLet G be a graph of size m and [Formula: see text] be the spectral radius of its adjacency matrix. A graph is said to be H-free if it does not contain a subgraph isomorphic to H. Let [Formula: see text] be the graph obtained by adding a pendent vertex to
Amir Rehman, S. Pirzada
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Line game-perfect graphs [PDF]
Discrete Mathematics & Theoretical Computer ScienceThe $[X,Y]$-edge colouring game is played with a set of $k$ colours on a graph $G$ with initially uncoloured edges by two players, Alice (A) and Bob (B). The players move alternately. Player $X\in\{A,B\}$ has the first move. $Y\in\{A,B,-\}$.
Stephan Dominique Andres, Wai Lam Fong
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On Minrank and Forbidden Subgraphs [PDF]
ACM Transactions on Computation Theory, 2019 The minrank over a field F of a graph G on the vertex set { 1,2,… , n } is the minimum possible rank of a matrix M ∈ F n × n such that M
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Relative timing information and orthology in evolutionary scenarios. [PDF]
Algorithms Mol Biol, 2023 Schaller D +5 more
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Complexity Framework for Forbidden Subgraphs I: The Framework
AlgorithmicaAbstract For a set of graphs $${\mathcal {H}}$$ H , a graph G is $${\mathcal {H}}$$ H -subgraph-free if G does not contain
Johnson, Matthew +6 more
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Discussiones Mathematicae Graph Theory, 2017 We characterize the class L32$L_3^2 $ of intersection graphs of hypergraphs with rank at most 3 and multiplicity at most 2 by means of a finite list of forbidden induced subgraphs in the class of threshold graphs.
Metelsky Yury +2 more
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