Results 61 to 70 of about 3,384,024 (197)
Equivalent Formulation of Thomassen's Conjecture Using Tutte Paths in Claw‐Free Graphs
Journal of Graph Theory, EarlyView.ABSTRACT We continue studying Thomassen's conjecture (every 4‐connected line graph has a Hamilton cycle) in the direction of a recently shown equivalence with Jackson's conjecture (every 2‐connected claw‐free graph has a Tutte cycle), and we extend the equivalent formulation as follows: In every connected claw‐free graph, any two vertices are connected
Adam Kabela +2 more
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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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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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A Note on Lovász Characterization of Perfect Graphs
Journal of Graph Theory, EarlyView.ABSTRACT A graph is perfect if, for every induced subgraph, the chromatic number equals the size of its largest clique. In 1972, Lovász established a fundamental characterization of perfect graphs, showing that a graph is perfect if and only if, for every induced subgraph, the product of the size of the largest independent set and the size of the ...
James Alex
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Characterization of Graphs Without Even F $F$‐Orientations
Journal of Graph Theory, EarlyView.ABSTRACT A graph G $G$ is 1‐extendable if every edge belongs to at least one 1‐factor of G $G$. Let G $G$ be a graph with a 1‐factor F $F$. Then an even (odd) F $F$ ‐orientation of G $G$ is an orientation in which each F $F$‐alternating cycle has exactly an even (odd) number of edges directed in the same fixed direction around the cycle.
Marién Abreu +3 more
wiley +1 more source
Journal of Graph Theory, EarlyView.ABSTRACT A 2‐edge‐coloured graph G $G$ is called locally complete if for each vertex v $v$, the vertices adjacent to v $v$ through edges of the same colour induce a complete subgraph in G $G$. Locally complete 2‐edge‐coloured graphs have nice properties, and there exists a polynomial algorithm to decide whether such a graph has an alternating ...
Jørgen Bang‐Jensen, Jing Huang
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Heuristic approaches for a new variant of the team orienteering problem
International Transactions in Operational Research, EarlyView.Abstract In this paper, we tackle the team orienteering problem (TOP) with service times, mandatory nodes and incompatibilities arising from two real‐world healthcare applications. We propose two heuristic algorithms: a variable neighbourhood descent algorithm and a matheuristic based on a cut separation approach.
Alberto Guastalla +2 more
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Generalizing forbidden induced subgraph characterizations of high throttling numbers
Australas. J Comb., 2022 Zero forcing is a process that models the spread of information throughout a graph as white vertices are forced to turn blue using a color change rule. The idea of throttling, introduced in 2013 by Butler and Young, is to optimize the trade-off between the number of initial blue vertices and the time taken to force all vertices to become blue.
Joshua Carlson, Jürgen Kritschgau
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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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Lower Bounds for Maximum Weight Bisections of Weighted Triangle‐Free Subcubic Graphs
Journal of Graph Theory, Volume 113, Issue 2, Page 252-273, October 2026.ABSTRACT A bisection of a graph is a cut in which the number of vertices in the two parts of the cut differ by at most 1. In this paper, we consider maximum weight bisections of edge‐weighted triangle‐free subcubic graphs and show that every weighted triangle‐free subcubic graph G = ( V , E , w )
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