Results 151 to 160 of about 1,017,247 (314)
Journal of Graph Theory, EarlyView.ABSTRACT In an effort to understand the complexity of the maximum independent set problem, Chvátal introduced t‐perfect graphs. While a full characterization of this class remains open, important progress has been made for claw‐free graphs [Bruhn and Stein, Math. Program. 2012] and P 5 ${P}_{5}$‐free graphs [Bruhn and Fuchs, SIAM J. Discrete Math. 2017]
Yixin Cao, Shenghua Wang
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On the irregularity of bipartite graphs
Discrete Mathematics, 2007 Let \(G=(V,E)\) be a finite simple graph. For \(u\in V\), let \(d(u)\) denote the valence of \(u\). For any edge \(e=uv\in E\), the imbalance of \(e\) is \(| d(u)-d(v)| \). The irregularity of \(G\), denoted \(\text{{irr}}(G)\), is the sum of the imbalances of the edges of \(G\). These notions are due to \textit{M. O. Albertson} [Ars Comb. 46, 219--225
Michael A. Henning, Dieter Rautenbach
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Tree Independence Number III. Thetas, Prisms and Stars
Journal of Graph Theory, EarlyView.ABSTRACT We prove that for every t ∈ N $t\in {\mathbb{N}}$ there exists τ = τ ( t ) ∈ N $\tau =\tau (t)\in {\mathbb{N}}$ such that every (theta, prism, K 1 , t ${K}_{1,t}$)‐free graph has tree independence number at most τ $\tau $ (where we allow “prisms” to have one path of length zero).
Maria Chudnovsky +2 more
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Algorithmic Aspects of Some Variants of Domination in Graphs
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2020 A set S ⊆ V is a dominating set in G if for every u ∈ V \ S, there exists v ∈ S such that (u, v) ∈ E, i.e., N[S] = V . A dominating set S is an isolate dominating set (IDS) if the induced subgraph G[S] has at least one isolated vertex.
Kumar J. Pavan, Reddy P.Venkata Subba
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The enumeration of bipartite graphs
Discrete Mathematics, 1979 AbstractThe standard construction of graphs with n connected components is modified here for bicolored graphs by letting Sn × H act on the function space Y∗where X={1,2,…,n}, Y is the set of connected bicolored graphs, and H is the group that interchanges the vertex colors.
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On Odd Covers of Cliques and Disjoint Unions
Journal of Graph Theory, EarlyView.ABSTRACT Babai and Frankl posed the “odd cover problem” of finding the minimum cardinality of a collection of complete bipartite graphs such that every edge of the complete graph of order n $n$ is covered an odd number of times. In a previous paper with O'Neill, some of the authors proved that this value is always ⌈ n / 2 ⌉ $\lceil n/2\rceil $ or ⌈ n /
Calum Buchanan +7 more
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International Journal of Applied Mathematics and Computer ScienceThis paper introduces the concept of filters in a rough bi-Heyting algebra. The rough bi-Heyting algebra defined through the rough semiring offers interesting properties.
Praba Bashyam +1 more
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Problem Definition and Optimization Method for Bipartite Graph Scheduling
IEEE AccessBipartite graphs can describe various systems in real world. In this study, we define a new problem class for optimizing the cost or profit associated with state changes in systems represented by bipartite graphs and propose a heuristic approach based on
Hiroshi Ikeda, Tatsuya Takanaga
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Journal of Chemistry, 2019 In this paper, with respect to the Wiener index, hyper-Wiener index, and Harary index, it gives some sufficient conditions for some graphs to be traceable, Hamiltonian, Hamilton-connected, or traceable for every vertex.
Guisheng Jiang, Lifang Ren, Guidong Yu
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Prediction of Shooting Events in Soccer Videos Using Complete Bipartite Graphs and Players' Spatial-Temporal Relations. [PDF]
Sensors (Basel), 2023 Goka R +4 more
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