Results 1 to 10 of about 20,911 (165)
The open monophonic chromatic number of a graph [PDF]
Journal of Hyperstructures, 2023 A set P of vertices in a connected graph G is called open monophonic chromatic set if P is both an open monophonic set and a chromatic set. The minimum cardinality among the set of all open monophonic chromatic sets is called open monophonic chromatic ...
Mohammed Abdul Khayyoom +1 more
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Tree‐Chromatic Number Is Not Equal to Path‐Chromatic Number* [PDF]
Journal of Graph Theory, 2017 AbstractFor a graph G and a tree‐decomposition of G, the chromatic number of is the maximum of , taken over all bags . The tree‐chromatic number of G is the minimum chromatic number of all tree‐decompositions of G. The path‐chromatic number of G is defined analogously.
Tony Huynh, Ringi Kim
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The Distinguishing Chromatic Number [PDF]
The Electronic Journal of Combinatorics, 2006 In this paper we define and study the distinguishing chromatic number, $\chi_D(G)$, of a graph $G$, building on the work of Albertson and Collins who studied the distinguishing number. We find $\chi_D(G)$ for various families of graphs and characterize those graphs with $\chi_D(G)$ $ = |V(G)|$, and those trees with the maximum chromatic distingushing ...
Karen L. Collins, Ann N. Trenk
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Local chromatic number and topology [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 The local chromatic number of a graph, introduced by Erdős et al., is the minimum number of colors that must appear in the closed neighborhood of some vertex in any proper coloring of the graph.
Gábor Simonyi, Gábor Tardos
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Properties of Large 2-Crossing-Critical Graphs
Journal of Graph Algorithms and Applications, 2022 A $c$-crossing-critical graph is one that has crossing number at least $c$ but each of its proper subgraphs has crossing number less than $c$. Recently, a set of explicit construction rules was identified by Bokal, Oporowski, Richter, and Salazar to ...
Drago Bokal +6 more
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The game chromatic number of trees and forests [PDF]
Discrete Mathematics & Theoretical Computer Science, 2015 While the game chromatic number of a forest is known to be at most 4, no simple criteria are known for determining the game chromatic number of a forest. We first state necessary and sufficient conditions for forests with game chromatic number 2 and then
Charles Dunn +4 more
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Chromatic-Choosability of Hypergraphs with High Chromatic Number [PDF]
The Electronic Journal of Combinatorics, 2019 It was conjectured by Ohba and confirmed by Noel, Reed and Wu that, for any graph $G$, if $|V(G)|\le 2\chi(G)+1$ then $G$ is chromatic-choosable; i.e., it satisfies $\chi_l(G)=\chi(G)$. This indicates that the graphs with high chromatic number are chromatic-choosable. We observe that this is also the case for uniform hypergraphs and further propose a
Wei Wang 0052, Jianguo Qian
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Distance graphs with maximum chromatic number [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 Let $D$ be a finite set of integers. The distance graph $G(D)$ has the set of integers as vertices and two vertices at distance $d ∈D$ are adjacent in $G(D)$.
Javier Barajas, Oriol Serra
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The -distance chromatic number of trees and cycles
AKCE International Journal of Graphs and Combinatorics, 2019 For any positive integer , a -distance coloring of a graph is a vertex coloring of in which no two vertices at distance less than or equal to receive the same color.
Niranjan P.K., Srinivasa Rao Kola
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Dynamic Chromatic Number of Bipartite Graphs [PDF]
Scientific Annals of Computer Science, 2016 A dynamic coloring of a graph G is a proper vertex coloring such that for every vertex v Î V(G) of degree at least 2, the neighbors of v receive at least 2 colors.
S. Saqaeeyan, E. Mollaahamdi
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