Results 91 to 100 of about 1,022,735 (236)
Discrete Applied Mathematics, 2015 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Blidia, Mostafa +2 more
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On Deeply Critical Oriented Graphs
Journal of Combinatorial Theory, Series B, 2001 The oriented chromatic number \(o(H)\) of an oriented graph (i.e. a digraph without opposite arcs) \(H\) is the minimum order of an oriented graph \(H'\) such that \(H\) has a homomorphism to \(H'\). In other words, \(o(H)\) is the minimum positive integer \(m\) such that there exists a proper (in usual sense) colouring \(f\) of \(V(H)\) with \(m ...
Borodin, O.V. +4 more
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Some Toughness Results in Independent Domination Critical Graphs
Discussiones Mathematicae Graph Theory, 2015 A subset S of V (G) is an independent dominating set of G if S is independent and each vertex of G is either in S or adjacent to some vertex of S. Let i(G) denote the minimum cardinality of an independent dominating set of G. A graph G is k-i-critical if
Ananchuen Nawarat +1 more
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Hamiltonicities of Double Domination Critical and Stable Claw-Free Graphs
Discussiones Mathematicae Graph Theory, 2019 A graph G with the double domination number γ×2(G) = k is said to be k- γ×2-critical if γ×2 (G + uv) < k for any uv ∉ E(G). On the other hand, a graph G with γ×2 (G) = k is said to be k-γ×2+$k - \gamma _{ \times 2}^ + $-stable if γ×2 (G + uv) = k for any
Kaemawichanurat Pawaton
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Inequalities of Independence Number, Clique Number and Connectivity of Maximal Connected Domination Critical Graphs [PDF]
, 2019 Norah Almalki, Pawaton Kaemawichanurat
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Lovász et al. proved that every $6$-edge-connected graph has a nowhere-zero $3$-flow. In fact, they proved a more technical statement which says that there exists a nowhere zero $3$-flow that extends the flow prescribed on the incident edges of a single vertex $z$ with bounded degree. We extend this theorem of Lovász et al.
Árnadóttir, Arnbjörg Soffía +5 more
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Size of edge-critical uniquely 3-colorable planar graphs [PDF]
, 2013 Zepeng Li +3 more
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Critical Graphs for Acyclic Colorings [PDF]
Canadian Mathematical Bulletin, 1978 The concept of acyclic colorings of graphs, introduced by Grunbaum [2], is a generalization of point-arboricity. An acyclic coloring of a graph is a proper coloring of its points such that there is no two-colored cycle. We denote by a(G), the acyclic chromatic number of a graph G, the minimum number of colors for an acyclic coloring of G.
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Spectral radius, fractional $[a,b]$-factor and ID-factor-critical graphs [PDF]
, 2023 Ao Fan, Ruifang Liu, Guoyan Ao
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