Results 91 to 100 of about 2,481 (263)
Influence of the tie-break rule on the end-vertex problem [PDF]
Discrete Mathematics & Theoretical Computer Science, 2014 End-vertices of a given graph search may have some nice properties, as for example it is well known that the last vertex of Lexicographic Breadth First Search (LBFS) in a chordal graph is simplicial, see Rose, Tarjan and Lueker 1976.
Pierre Charbit +2 more
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On b-perfect Chordal Graphs [PDF]
Graphs and Combinatorics, 2009 The b-chromatic number of a graph G is the largest integer k such that G has a coloring of the vertices in k color classes such that every color class contains a vertex that has a neighbour in all other color classes. We characterize the class of chordal graphs for which the b-chromatic number is equal to the chromatic number for every induced subgraph.
Maffray, Frédéric, Mechebbek, Meriem
openaire +3 more sources
Stable Cuts, NAC‐Colourings and Flexible Realisations of Graphs
Journal of Graph Theory, EarlyView.ABSTRACT A (2‐dimensional) realisation of a graph G $G$ is a pair ( G , p ) $(G,p)$, where p $p$ maps the vertices of G $G$ to R 2 ${{\mathbb{R}}}^{2}$. A realisation is flexible if it can be continuously deformed while keeping the edge lengths fixed, and rigid otherwise.
Katie Clinch +5 more
wiley +1 more source
Discussiones Mathematicae Graph Theory, 2016 We study domination between different types of walks connecting two non-adjacent vertices u and v of a graph (shortest paths, induced paths, paths, tolled walks).
Alcón Liliana
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Weak Degeneracy of Planar Graphs
Journal of Graph Theory, EarlyView.ABSTRACT The weak degeneracy of a graph G $G$ is a numerical parameter that was recently introduced by the first two authors with the aim of understanding the power of greedy algorithms for graph coloring. Every d $d$‐degenerate graph is weakly d $d$‐degenerate, but the converse is not true in general (e.g., all connected d $d$‐regular graphs except ...
Anton Bernshteyn +2 more
wiley +1 more source
On the 2-token graph of a graph
AKCE International Journal of Graphs and Combinatorics, 2020 Let be a graph and let be a positive integer. Let = and . The -token graph is the graph with vertex set and two vertices and are adjacent if and , where denotes the symmetric difference. In this paper we present several basic results on 2-token graphs.
J. Deepalakshmi +3 more
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A Min–Max Relation on Dicuts and Dijoins in Weighted Chordal Digraphs
Journal of Graph Theory, EarlyView.ABSTRACT In a digraph, a dicut is a cut where all the arcs cross in one direction. A dijoin is a subset of arcs that intersects every dicut. Edmonds and Giles conjectured that in a weighted digraph, the minimum weight of a dicut is equal to the maximum size of a packing of dijoins. This has been disproved. However, the unweighted version conjectured by
Gérard Cornuéjols, Siyue Liu, R. Ravi
wiley +1 more source
Chordal Completions of Planar Graphs
Journal of Combinatorial Theory, Series B, 1994 A graph is chordal if there are no induced cycles of length 4 or more. A chordal completion of a graph is formed by adding edges until the resulting graph is chordal. What is the minimal number of edges in a chordal completion? The authors answer this question for the class of planar graphs: every planar graph on \(n\) vertices has a chordal completion
Fan R. K. Chung, David Mumford
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Journal of Plant Nutrition and Soil Science, EarlyView.We provide a historic overview of microscopic soil structure characterization from its founding father, Walter Kubiëna, to several technical revolutions like automation, digitalization, and artificial intelligence. In addition to technical advancements, we explore how concepts and research questions have evolved in time.
Steffen Schlüter +3 more
wiley +1 more source
PLANTS, PEOPLE, PLANET, EarlyView.Arboreta bridge people and nature while conserving tree biodiversity, supporting climate resilience, and advancing environmental education. This study maps over a century of available and indexed arboretum research, uncovering trends, knowledge gaps, and opportunities for collaboration.
Catarina Patoilo Teixeira +1 more
wiley +1 more source