Results 21 to 30 of about 9,006,025 (294)
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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Game Chromatic Number of Shackle Graphs
JTAM (Jurnal Teori dan Aplikasi Matematika), 2021 Coloring vertices on graph is one of the topics of discrete mathematics that are still developing until now. Exploration Coloring vertices develops in the form of a game known as a coloring game. Let G graph.
Firmansyah Firmansyah, Abdul Mujib
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The fractional chromatic number of triangle-free subcubic graphs [PDF]
, 2014 Heckman and Thomas conjectured that the fractional chromatic number of any triangle-free subcubic graph is at most 14 / 5. Improving on estimates of Hatami and Zhu and of Lu and Peng, we prove that the fractional chromatic number of any triangle-free ...
Král’, Daniel +5 more
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The Locating Chromatic Number for Pizza Graphs [PDF]
, 2023 The location chromatic number for a graph is an extension of the concepts of partition dimension and vertex coloring in a graph. The minimum number of colors required to perform location coloring in graph G is referred to as the location chromatic number
Nasution, Hamidah +3 more
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Separating tree-chromatic number from path-chromatic number [PDF]
Journal of Combinatorial Theory, Series B, 2019 We apply Ramsey theoretic tools to show that there is a family of graphs which have tree-chromatic number at most~$2$ while the path-chromatic number is unbounded. This resolves a problem posed by Seymour.
Fidel Barrera-Cruz +6 more
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