Results 61 to 70 of about 566 (185)
Preorder induced by rainbow forbidden subgraphs
Discrete MathematicsA subgraph $H$ of an edge-colored graph $G$ is rainbow if all the edges of $H$ receive different colors. If $G$ does not contain a rainbow subgraph isomorphic to $H$, we say that $G$ is rainbow $H$-free. For connected graphs $H_1$ and $H_2$, if every rainbow $H_1$-free edge-colored complete graph colored in sufficiently many colors is rainbow $H_2 ...
Shun-ichi Maezawa, Akira Saito
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Edge‐Length Preserving Embeddings of Graphs Between Normed Spaces
Journal of Graph Theory, Volume 112, Issue 4, Page 491-506, August 2026.ABSTRACT The concept of graph embeddability, initially formalized by Belk and Connelly and later expanded by Sitharam and Willoughby, extends the question of embedding finite metric spaces into a given normed space. A finite simple graph G = ( V , E ) is said to be ( X , Y )‐embeddable if any set of induced edge lengths from an embedding of G into a ...
Sean Dewar +3 more
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Journal of Graph Theory, Volume 112, Issue 3, Page 198-208, July 2026.ABSTRACT We prove that the Ramsey number R ( 5 , 5 ) is less than or equal to 46. The proof uses a combination of linear programming and checking a large number of cases by computer. All of the computational parts of the proof were independently implemented by both authors, with consistent results.
Vigleik Angeltveit, Brendan D. McKay
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Discussiones Mathematicae Graph Theory, 2017 We characterize the class L32$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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Towards Characterization of Five‐List‐Colorability of Toroidal Graphs
Journal of Graph Theory, Volume 112, Issue 3, Page 267-275, July 2026.ABSTRACT Through computer‐assisted enumeration, we list minimal obstructions for 5‐choosability of graphs on the torus with the following additional property: There exists a cyclic system of non‐contractible triangles around the torus where the consecutive triangles are at distance at most four.
Zdeněk Dvořák +1 more
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Treewidth Versus Clique Number. V. Further Connections With Tree‐Independence Number
Journal of Graph Theory, Volume 112, Issue 3, Page 337-351, July 2026.ABSTRACT We continue the study of ( tw , ω )‐bounded graph classes, that is, hereditary graph classes in which large treewidth is witnessed by the presence of a large clique, and the relation of this property to boundedness of the tree‐independence number, a graph parameter introduced independently by Yolov in 2018 and by Dallard, Milanič, and Štorgel ...
Claire Hilaire +2 more
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Compatible Spanning Circuits and Forbidden Induced Subgraphs
Graphs and CombinatoricsAbstractA compatible spanning circuit in an edge-colored graph G (not necessarily properly) is defined as a closed trail containing all vertices of G in which any two consecutively traversed edges have distinct colors. The existence of extremal compatible spanning circuits (i.e., compatible Hamilton cycles and compatible Euler tours) has been studied ...
Zhiwei Guo +3 more
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On the validity of Lovász’s inequality for induced star-perfect graphs
Journal of Inequalities and ApplicationsLet F $\mathcal{F}$ be a family of graphs. For a graph G, define θ F ( G ) $\theta _{F}(G)$ as the minimum number of induced subgraphs of G, each isomorphic to a member of F $\mathcal{F}$ , needed to cover V ( G ) $V(G)$ , and α F ( G ) $\alpha _{F}(G ...
James Alex, Louis Caccetta
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Strategic Management Journal, Volume 47, Issue 7, Page 1840-1877, July 2026.Abstract Research Summary We extend ecosystem theory to cases in which platforms are complementors to each other: inter‐platform ecosystems. Analyzing web traffic data on 241 European platforms, we identify and characterize demand‐side inter‐platform ecosystems, and propose a theory of why they emerge.
Bruno Carballa‐Smichowski +3 more
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The Independence Ratio of 4‐Cycle‐Free Planar Graphs
Journal of Graph Theory, Volume 112, Issue 2, Page 116-127, June 2026.ABSTRACT We prove that every n‐vertex planar graph G with no triangle sharing an edge with a 4‐cycle has independence ratio n ∕ α ( G ) ≤ 4 − ε for ε = 1 ∕ 30. This result implies that the same bound holds for 4‐cycle‐free planar graphs and planar graphs with no adjacent triangles and no triangle sharing an edge with a 5‐cycle.
Tom Kelly +3 more
wiley +1 more source