Results 21 to 30 of about 208 (79)
An Improved Upper Bound on Neighbor Expanded Sum Distinguishing Index
Discussiones Mathematicae Graph Theory, 2020 A total k-weighting f of a graph G is an assignment of integers from the set {1, . . . , k} to the vertices and edges of G. We say that f is neighbor expanded sum distinguishing, or NESD for short, if Σw∈N(v) (f(vw) + f(w)) differs from Σw∈N(u)(f(uw) + f(
Vučković Bojan
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More on the Minimum Size of Graphs with Given Rainbow Index
Discussiones Mathematicae Graph Theory, 2020 The concept of k-rainbow index rxk(G) of a connected graph G, introduced by Chartrand et al., is a natural generalization of the rainbow connection number of a graph.
Zhao Yan
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Sum-List Colouring of Unions of a Hypercycle and a Path with at Most Two Vertices in Common
Discussiones Mathematicae Graph Theory, 2020 Given a hypergraph and a function f : V () → , we say that is f-choosable if there is a proper vertex colouring ϕ of such that ϕ (v) ∈ L(v) for all v ∈ V (), where L : V () → 2 is any assignment of f(v) colours to a vertex v.
Drgas-Burchardt Ewa +1 more
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Maximum Edge-Colorings Of Graphs
Discussiones Mathematicae Graph Theory, 2016 An r-maximum k-edge-coloring of G is a k-edge-coloring of G having a property that for every vertex v of degree dG(v) = d, d ≥ r, the maximum color, that is present at vertex v, occurs at v exactly r times. The r-maximum index χr′(G)$\chi _r^\prime (G)$
Jendrol’ Stanislav +1 more
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Facial Incidence Colorings of Embedded Multigraphs
Discussiones Mathematicae Graph Theory, 2019 Let G be a cellular embedding of a multigraph in a 2-manifold. Two distinct edges e1, e2 ∈ E(G) are facially adjacent if they are consecutive on a facial walk of a face f ∈ F(G). An incidence of the multigraph G is a pair (v, e), where v ∈ V (G), e ∈ E(G)
Jendrol’ Stanislav +2 more
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On the ρ-Edge Stability Number of Graphs
Discussiones Mathematicae Graph Theory, 2022 For an arbitrary invariant ρ(G) of a graph G the ρ-edge stability number esρ(G) is the minimum number of edges of G whose removal results in a graph H ⊆ G with ρ(H) ≠ ρ(G) or with E(H) = ∅.
Kemnitz Arnfried, Marangio Massimiliano
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Tr-Span of Directed Wheel Graphs
Discussiones Mathematicae Graph Theory, 2018 In this paper, we consider T-colorings of directed graphs. In particular, we consider as a T-set the set Tr = {0, 1, 2, . . ., r−1, r+1, . . .}. Exact values and bounds of the Tr-span of directed graphs whose underlying graph is a wheel graph are ...
Besson Marc, Tesman Barry
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Improved Bounds for Some Facially Constrained Colorings
Discussiones Mathematicae Graph Theory, 2023 A facial-parity edge-coloring of a 2-edge-connected plane graph is a facially-proper edge-coloring in which every face is incident with zero or an odd number of edges of each color. A facial-parity vertex-coloring of a 2-connected plane graph is a proper
Štorgel Kenny
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On the logical strengths of partial solutions to mathematical problems
Transactions of the London Mathematical Society, Volume 4, Issue 1, Page 30-71, December 2017., 2017 Abstract We use the framework of reverse mathematics to address the question of, given a mathematical problem, whether or not it is easier to find an infinite partial solution than it is to find a complete solution. Following Flood [‘Reverse mathematics and a Ramsey‐type König's lemma’, J. Symb. Log.
Laurent Bienvenu +2 more
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List Star Edge-Coloring of Subcubic Graphs
Discussiones Mathematicae Graph Theory, 2018 A star edge-coloring of a graph G is a proper edge coloring such that every 2-colored connected subgraph of G is a path of length at most 3. For a graph G, let the list star chromatic index of G, ch′st(G), be the minimum k such that for any k-uniform ...
Kerdjoudj Samia +2 more
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