Results 11 to 20 of about 38,756 (312)
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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Dual Perfect Bases and Dual Perfect Graphs [PDF]
Moscow Mathematical Journal, 2015 We introduce the notion of dual perfect bases and dual perfect graphs. We show that every integrable highest weight module $V_q( )$ over a quantum generalized Kac-Moody algebra $U_{q}(\mathcal{g})$ has a dual perfect basis and its dual perfect graph is isomorphic to the crystal $B( )$.
Byeong Hoon Kahng +3 more
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Contractions in Perfect Graphs
Discrete Applied MathematicsIn this paper, we characterize the class of {\em contraction perfect} graphs which are the graphs that remain perfect after the contraction of any edge set. We prove that a graph is contraction perfect if and only if it is perfect and the contraction of any single edge preserves its perfection.
Alexandre Dupont-Bouillard +3 more
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Perfect Roman domination in middle graphs [PDF]
Discrete Mathematics Letters, 2021 Kijung Kim
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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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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 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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