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Graphs with tiny vector chromatic numbers and huge chromatic numbers [PDF]
The 43rd Annual IEEE Symposium on Foundations of Computer Science, 2002. Proceedings., 2003 Summary: \textit{D. Karger, R. Motwani} and \textit{M. Sudan} [J. ACM 45, 246--265 (1998; Zbl 0904.68116)] introduced the notion of a vector coloring of a graph. In particular, they showed that every \(k\)-colorable graph is also vector \(k\)-colorable, and that for constant \(k\), graphs that are vector \(k\)-colorable can be colored by roughly ...
Feige, Uriel +2 more
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Fuzzy coloring and total fuzzy coloring of various types of intuitionistic fuzzy graphs [PDF]
Notes on IFS, 2023 In this paper, fuzzy coloring and total fuzzy coloring of intuitionistic fuzzy graphs are introduced. The fuzzy chromatic number, fuzzy chromatic index, total fuzzy chromatic number and total fuzzy chromatic index of both vertices and edges in ...
R. Buvaneswari, P. Revathy
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On the fractional chromatic number, the chromatic number, and graph products
Discrete Mathematics, 2002 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Sandi Klavzar, Hong-Gwa Yeh
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Circular Chromatic Numbers and Fractional Chromatic Numbers of Distance Graphs
European Journal of Combinatorics, 1998 This paper studies the circular (or star) chromatic numbers and fractional chromatic numbers of distance graphs \(G(Z, D)\) for various sets \(D\) (being the graph with vertex set a subset of the integers, and two vertices \(x\), \(y\) being adjacent iff \(| x-y|\in D\)). Various specific cases are calculated, including all cases when \(| D|= 2\).
Chang, Gerard J. +2 more
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Total dominator chromatic number of a graph [PDF]
Transactions on Combinatorics, 2015 Given a graph $G$, the total dominator coloring problem seeks a proper coloring of $G$ with the additional property that every vertex in the graph is adjacent to all vertices of a color class. We seek to minimize the number of color classes.
Adel P. Kazemi
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Unified Spectral Bounds on the Chromatic Number
Discussiones Mathematicae Graph Theory, 2015 One of the best known results in spectral graph theory is the following lower bound on the chromatic number due to Alan Hoffman, where μ1 and μn are respectively the maximum and minimum eigenvalues of the adjacency matrix: χ ≥ 1+μ1/−μn.
Elphick Clive, Wocjan Pawel
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Trees with Certain Locating-chromatic Number
Journal of Mathematical and Fundamental Sciences, 2016 The locating-chromatic number of a graph G can be defined as the cardinality of a minimum resolving partition of the vertex set V(G) such that all vertices have distinct coordinates with respect to this partition and every two adjacent vertices in G are ...
Dian Kastika Syofyan +2 more
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A Tight Bound on the Set Chromatic Number
Discussiones Mathematicae Graph Theory, 2013 We provide a tight bound on the set chromatic number of a graph in terms of its chromatic number. Namely, for all graphs G, we show that χs(G) > ⌈log2 χ(G)⌉ + 1, where χs(G) and χ(G) are the set chromatic number and the chromatic number of G ...
Sereni Jean-Sébastien +1 more
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ON LOCAL ANTIMAGIC CHROMATIC NUMBER OF GRAPHS [PDF]
Journal of Algebraic Systems, 2020 A {it local antimagic labeling} of a connected graph $G$ with at least three vertices, is a bijection $f:E(G) rightarrow {1,2,ldots , |E(G)|}$ such that for any two adjacent vertices $u$ and $v$ of $G$, the condition $omega _{f}(u) neq omega _{f}(v ...
S. Shaebani
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Weighted graphs: Eigenvalues and chromatic number
Electronic Journal of Graph Theory and Applications, 2016 We revisit Hoffman relation involving chromatic number $\chi$ and eigenvalues. We construct some graphs and weighted graphs such that the largest and smallest eigenvalues $\lambda$ dan $\mu$ satisfy $\lambda=(1-\chi)\mu.$ We study in particular the ...
Charles Delorme
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