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Discussiones Mathematicae Graph Theory, 2013 Given a graph G = (V,E) and a set Lv of admissible colors for each vertex v ∈ V (termed the list at v), a list coloring of G is a (proper) vertex coloring ϕ : V → S v2V Lv such that ϕ(v) ∈ Lv for all v ∈ V and ϕ(u) 6= ϕ(v) for all uv ∈ E.
Tuza Zsolt
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Domatically perfect graphs [PDF]
AKCE International Journal of Graphs and Combinatorics, 2020 A graph of order is domatically perfect if , where and denote the domination number and the domatic number, respectively. In this paper, we give basic results for domatically perfect graphs, and study a main problem; for a given graph , to find a ...
Naoki Matsumoto
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Electronic Journal of Graph Theory and ApplicationsA perfect dominating set in a graph G = (V, E) is a subset S ⊆ V such that each vertex in V \ S has exactly one neighbor in S. A perfect coalition in G consists of two disjoint sets of vertices V1 and V2 such that i) neither V1 nor V2 is a dominating set,
Doost Ali Mojdeh +1 more
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Strong Perfect Cobondage Number of Standard Graphs
Ratio Mathematica, 2023 Let G be a simple graph. A subset S Í V(G) is called a strong (weak) perfect dominating set of G if |Ns(u) ∩ S| = 1(|Nw(u) ∩ S| = 1) for every u ∊V(G) - S where Ns(u) = {v ∊ V(G) / uv deg v ≥ deg u} (Nw(u) = {v ∊V(G) / uv deg v ≤ deg u}.
T. S Govindalakshmi, N Meena
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Perfect Nilpotent Graphs [PDF]
Kragujevac Journal of Mathematics, 2021 Let R be a commutative ring with identity. The nilpotent graph of R, denoted by ΓN(R), is a graph with vertex set ZN(R)∗, and two vertices x and y are adjacent if and only if xy is nilpotent, where ZN(R) = {x ∈ R∣xy is nilpotent, for some y ∈ R∗}. A perfect graph is a graph in which the chromatic number of every induced subgraph equals the size of the ...
Nikmehr, M. J., Azadi, A.
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Journal of Combinatorial Theory, Series B, 2018 Let $G=(V,E)$ be a graph and let $A_G$ be the clique-vertex incidence matrix of $G$. It is well known that $G$ is perfect iff the system $A_{_G}\mathbf x\le \mathbf 1$, $\mathbf x\ge\mathbf0$ is totally dual integral (TDI). In 1982, Cameron and Edmonds proposed to call $G$ box-perfect if the system $A_{_G}\mathbf x\le \mathbf 1$, $\mathbf x\ge\mathbf0$
Guoli Ding, Wenan Zang, Qiulan Zhao
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Perfect folding of graphs [PDF]
Delta Journal of Science, 2019 In this paper we introduced the definition of perfect foldingof graphs and we proved that cycle graphs of even number ofedges can be perfectly folded while that of odd number ofedges can be perfectly folded to C3 .
H. Ahmed, E. M. El-Kholy
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Perfect double Italian domination of a graph
AKCE International Journal of Graphs and Combinatorics, 2023 For a graph [Formula: see text] with [Formula: see text] and [Formula: see text], a perfect double Italian dominating function is a function [Formula: see text] having the property that [Formula: see text], for every vertex [Formula: see text] with ...
Guoliang Hao +2 more
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Total perfect codes in graphs realized by commutative rings [PDF]
Transactions on Combinatorics, 2022 Let $R$ be a commutative ring with unity not equal to zero and let $\Gamma(R)$ be a zero-divisor graph realized by $R$. For a simple, undirected, connected graph $G = (V, E)$, a {\it total perfect code} denoted by $C(G)$ in $G$ is a subset $C(G ...
Rameez Raja
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Perfect Fuzzy Soft Tripartite Graphs and Their Complements
Discrete Dynamics in Nature and Society, 2022 Fuzzy soft graphs are efficient numerical tools for simulating the uncertainty of the real world. A fuzzy soft graph is a perfect fusion of the fuzzy soft set and the graph model that is widely used in a variety of fields.
Kalaichelvan Kalaiarasi +4 more
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