Results 31 to 40 of about 119,953 (318)
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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0034 | Chromatic Number and Neutrosophic Chromatic Number
, 2021 New setting is introduced to study chromatic number. Neutrosophic chromatic number and chromatic number are proposed in this way, some results are obtained. Classes of neutrosophic graphs are used to obtains these numbers and the representatives of the colors. Using colors to assigns to the vertices of neutrosophic graphs is applied. Some questions and
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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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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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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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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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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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Oriented chromatic number of Halin graphs
, 2013 Oriented chromatic number of an oriented graph $G$ is the minimum order of an oriented graph $H$ such that $G$ admits a homomorphism to $H$. The oriented chromatic number of an unoriented graph $G$ is the maximal chromatic number over all possible ...
Dybizbański, Janusz +1 more
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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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