Results 41 to 50 of about 3,613,364 (137)
Certifying Induced Subgraphs in Large Graphs
Journal of Graph Algorithms and ApplicationsWe introduce I/O-efficient certifying algorithms for the recognition of bipartite, split, threshold, bipartite chain, and trivially perfect graphs. When the input graph is a member of the respective class, the certifying algorithm returns a certificate
Ulrich Meyer +2 more
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Discussiones Mathematicae Graph Theory, 2017 We characterize the class L32$L_3^2 $ of intersection graphs of hypergraphs with rank at most 3 and multiplicity at most 2 by means of a finite list of forbidden induced subgraphs in the class of threshold graphs.
Metelsky Yury +2 more
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Heuristic approaches for a new variant of the team orienteering problem
International Transactions in Operational Research, Volume 34, Issue 2, Page 975-1002, March 2027.Abstract In this paper, we tackle the team orienteering problem (TOP) with service times, mandatory nodes and incompatibilities arising from two real‐world healthcare applications. We propose two heuristic algorithms: a variable neighbourhood descent algorithm and a matheuristic based on a cut separation approach.
Alberto Guastalla +2 more
wiley +1 more source
A Forbidden Subgraph Characterization Problem and a Minimal-Element Subset of Universal Graph Classes [PDF]
, 2004 The direct sum of a finite number of graph classes H_1, ..., H_k is defined as the set of all graphs formed by taking the union of graphs from each of the H_i. The join of these graph classes is similarly defined as the set of all graphs formed by taking
Barrus, Michael D.
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Maximum induced subgraph of a recursive circulant
, 2005 The recursive circulant RC(2(n), 4) enjoys several attractive topological properties. Let max_epsilon(G) (m) denote the maximum number of edges in a subgraph of graph G induced by m nodes. In this paper, we show that max_epsilon(RC(2n,4))(m) = Sigma(i)(r)
Yang, X. +5 more
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On the validity of Lovász’s inequality for induced star-perfect graphs
Journal of Inequalities and ApplicationsLet F $\mathcal{F}$ be a family of graphs. For a graph G, define θ F ( G ) $\theta _{F}(G)$ as the minimum number of induced subgraphs of G, each isomorphic to a member of F $\mathcal{F}$ , needed to cover V ( G ) $V(G)$ , and α F ( G ) $\alpha _{F}(G ...
James Alex, Louis Caccetta
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Journal of Graph Theory, Volume 113, Issue 4, Page 553-570, December 2026.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‐free graphs [Bruhn and Fuchs, SIAM J. Discrete Math. 2017]. We take
Yixin Cao, Shenghua Wang
wiley +1 more source
Chromatic Ramsey Numbers and Two‐Color Turán Densities
Journal of Graph Theory, Volume 113, Issue 4, Page 663-676, December 2026.ABSTRACT Given a graph G, its 2‐color Turán number ex ( 2 ) ( n , G ) is the maximum number of edges in an n‐vertex graph, such that the edges can be colored with two colors avoiding a monochromatic copy of G. Let π ( 2 ) ( G ) = lim n → ∞ ex ( 2 ) ( n , G ) / n 2 be the 2‐color Turán density of G.
Maria Axenovich, Simon Gaa, Dingyuan Liu
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Forbidden induced subgraphs for threshold-like graph classes [PDF]
, 2019 Every hereditary graph class (closed under induced subgraphs) has a characterization by forbidden induced subgraphs: graphs not in the class but every graph obtained by deleting a vertex is in the class.
Sivaraman, Vaidyanathan
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On Hereditary Helly classes of graphs
Discrete Mathematics & Theoretical Computer Science, 2008 In graph theory, the Helly property has been applied to families of sets, such as cliques, disks, bicliques, and neighbourhoods, leading to the classes of clique-Helly, disk-Helly, biclique-Helly, neighbourhood-Helly graphs, respectively.
Marina Groshaus, Jayme Luiz Szwarcfiter
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