Results 51 to 60 of about 258 (128)
Hardness Results and Spectral Techniques for Combinatorial Problems on Circulant Graphs
, 1998 We show that computing (and even approximating) MAXIMUM CLIQUE and MINIMUM GRAPH COLORING for circulant graphs is essentially as hard as in the general case.
Ivan Gerace +8 more
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Pair L(2, 1)-Labelings of Infinite Graphs
Discussiones Mathematicae Graph Theory, 2019 An L(2, 1)-labeling of a graph G = (V,E) is an assignment of nonnegative integers to V such that two adjacent vertices must receive numbers (labels) at least two apart and further, if two vertices are in distance 2 then they receive distinct labels. This
Yeh Roger K.
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Global Dominator Coloring of Graphs
Discussiones Mathematicae Graph Theory, 2019 Let S ⊆ V. A vertex v ∈ V is a dominator of S if v dominates every vertex in S and v is said to be an anti-dominator of S if v dominates none of the vertices of S. Let 𝒞 = (V1, V2, . . ., Vk) be a coloring of G and let v ∈ V (G).
Hamid Ismail Sahul, Rajeswari Malairaj
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On parsimonious edge-colouring of graphs with maximum degree three
, 2013 Revised version submitted to Graphs and CombinatoricsInternational audienceIn a graph $G$ of maximum degree $\Delta$ let $\gamma$ denote the largest fraction of edges that can be $\Delta$ edge-coloured.
Fouquet, Jean-Luc, Vanherpe, Jean-Marie
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On θ-commutators and the corresponding non-commuting graphs
Open Mathematics, 2017 The θ-commutators of elements of a group with respect to an automorphism are introduced and their properties are investigated. Also, corresponding to θ-commutators, we define the θ-non-commuting graphs of groups and study their correlations with other ...
Shalchi S., Erfanian A., Farrokhi DG M.
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On Color Energy of Few Classes of Bipartite Graphs and Corresponding Color Complements
, 2019 For a given colored graph G, the color energy is defined as Ec(G) = Σλi, for i = 1, 2,…., n; where λi is a color eigenvalue of the color matrix of G, Ac (G) with entries as 1, if both the corresponding vertices are neighbors and have different colors; -1,
Prajakta Bharat Joshi, Mayamma Joseph
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Irreducible No-Hole L(2, 1)-Coloring of Edge-Multiplicity-Paths-Replacement Graph
Discussiones Mathematicae Graph Theory, 2018 An L(2, 1)-coloring (or labeling) of a simple connected graph G is a mapping f : V (G) → Z+ ∪ {0} such that |f(u)−f(v)| ≥ 2 for all edges uv of G, and |f(u) − f(v)| ≥ 1 if u and v are at distance two in G.
Mandal Nibedita, Panigrahi Pratima
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Chromatic Properties of the Pancake Graphs
Discussiones Mathematicae Graph Theory, 2017 Chromatic properties of the Pancake graphs Pn, n ⩾ 2, that are Cayley graphs on the symmetric group Symn generated by prefix-reversals are investigated in the paper.
Konstantinova Elena
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Linear List Coloring of Some Sparse Graphs
Discussiones Mathematicae Graph Theory, 2021 A linear k-coloring of a graph is a proper k-coloring of the graph such that any subgraph induced by the vertices of any pair of color classes is a union of vertex-disjoint paths. A graph G is linearly L-colorable if there is a linear coloring c of G for
Chen Ming, Li Yusheng, Zhang Li
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Conflict-Free Vertex Connection Number At Most 3 and Size of Graphs
Discussiones Mathematicae Graph Theory, 2021 A path in a vertex-coloured graph is called conflict-free if there is a colour used on exactly one of its vertices. A vertex-coloured graph is said to be conflict-free vertex-connected if any two distinct vertices of the graph are connected by a conflict-
Doan Trung Duy, Schiermeyer Ingo
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