Results 51 to 60 of about 1,022,735 (236)
Critically partitionable graphs, I
Journal of Combinatorial Theory, Series B, 1979 AbstractA graph G is l-degenerate if τ(H)⩽l for all subgraphs H of G. A graph is said to be (k, l)-unique if V(G) has exactly one partition into k subsets V1,…, Vk such that each subset spans an l-degenerate graph. Extending a long sequence of results about graphs with high girth and high chromatic number, Bollobás and Thomason [4] proved the existence
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On Cotree-Critical and DFS Cotree-Critical Graphs [PDF]
Journal of Graph Algorithms and Applications, 2003 We give a characterization of DFS cotree-critical graphs which is central to the linear time Kuratowski finding algorithm implemented in PIGALE (Public Implementation of a Graph Algorithm Library and Editor) by the authors, and deduce an algorithm for finding a Kuratowski subdivision in a DFS cotree-critical graph.
de Fraysseix, Hubert +1 more
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Some results on the independence number of connected domination critical graphs
AKCE International Journal of Graphs and Combinatorics, 2018 A --critical graph is a graph with connected domination number and for any pair of non-adjacent vertices and of . Let and be respectively the clique number and the independence number of a graph.
P. Kaemawichanurat, T. Jiarasuksakun
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4-Factor-criticality of vertex-transitive graphs [PDF]
, 2014 A graph of order $n$ is $p$-factor-critical, where $p$ is an integer of the same parity as $n$, if the removal of any set of $p$ vertices results in a graph with a perfect matching.
Sun, Wuyang, Zhang, Heping
core
Journal of Combinatorial Theory, Series B, 1983 AbstractA set of vertices S is said to dominate the graph G if for each v ∉ S, there is a vertex u ∈ S with u adjacent to v. The smallest cardinality of any such dominating set is called the domination number of G and is denoted by γ(G). The purpose of this paper is to initiate an investigation of those graphs which are critical in the following sense:
Sumner, David P, Blitch, Pattie
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Point Arboricity Critical Graphs Exist [PDF]
Journal of the London Mathematical Society, 1975 Peer Reviewed ; http://deepblue.lib.umich.edu/bitstream/2027.42/135411/1/jlms0097 ...
Bollobás, Béla, Harary, Frank
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Characterizing graphs of critical pairs of layered generalized crowns
AKCE International Journal of Graphs and Combinatorics, 2020 The generalized crown is a well-known family of bipartite graphs whose order dimension is given in terms of the parameters and . In recent work, Garcia and Silva defined the notion of layering generalized crowns, producing multipartite posets called ...
Rebecca E. Garcia +3 more
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Small clique number graphs with three trivial critical ideals [PDF]
, 2013 The critical ideals of a graph are the determinantal ideals of the generalized Laplacian matrix associated to a graph. In this article we provide a set of minimal forbidden graphs for the set of graphs with at most three trivial critical ideals.
Carlos, Carlos A. Alfaro, E. Valencia
core
Journal of Combinatorial Theory, Series B, 2016 Un gráfico se llama diámetro-k-crítico si su diámetro es k, y la eliminación de cualquier borde aumenta estrictamente el diámetro. En este trabajo, probamos varios resultados relacionados con una conjetura a menudo atribuida a Murty y Simon, con respecto al número máximo de aristas que puede tener cualquier gráfico de diámetro k crítico. En particular,
Po‐Shen Loh, Jie Ma
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MEJ (Mathematics Education Journal), 2020 This research aims to describe the level of understanding the concept and critical thinking in resolving trigonometric equations using graphs. Tests and interviews were conducted to search for data and study more in the ability to understand the concepts
Maulida Luka Yusrina +2 more
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