Results 111 to 120 of about 10,088 (246)
Essentially tight bounds for rainbow cycles in proper edge‐colourings
Proceedings of the London Mathematical Society, Volume 130, Issue 4, April 2025.Abstract An edge‐coloured graph is said to be rainbow if no colour appears more than once. Extremal problems involving rainbow objects have been a focus of much research over the last decade as they capture the essence of a number of interesting problems in a variety of areas.
Noga Alon +4 more
wiley +1 more source
Domination in graphoidally covered graphs: Least-kernel graphoidal graphs-II
AKCE International Journal of Graphs and Combinatorics, 2018 Given a graph , not necessarily finite, a graphoidal cover of means a collection of non-trivial paths in called -edges, which are not necessarily open (not necessarily finite), such that every vertex of is an internal vertex of at most one path in and ...
Purnima Gupta, Rajesh Singh
doaj +2 more sources
Forbidden subgraphs for constant domination number
Discrete Mathematics & Theoretical Computer Science, 2018 In this paper, we characterize the sets $\mathcal{H}$ of connected graphs such that there exists a constant $c=c(\mathcal{H})$ satisfying $\gamma (G)\leq c$ for every connected $\mathcal{H}$-free graph $G$, where $\gamma (G)$ is the domination number of $G$.Comment: 6 pages, 1 ...
openaire +5 more sources
Forbidden subgraphs and the König–Egerváry property
Discrete Applied Mathematics, 2013 The matching number of a graph is the maximum size of a set of vertex-disjoint edges. The transversal number is the minimum number of vertices needed to meet every edge. A graph has the Konig-Egervary property if its matching number equals its transversal number.
Luciano N. Grippo +8 more
openaire +8 more sources
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
doaj
$2$-polarity and algorithmic aspects of polarity variants on cograph superclasses [PDF]
Discrete Mathematics & Theoretical Computer ScienceA graph $G$ is said to be an $(s, k)$-polar graph if its vertex set admits a partition $(A, B)$ such that $A$ and $B$ induce, respectively, a complete $s$-partite graph and the disjoint union of at most $k$ complete graphs.
Fernando Esteban Contreras-Mendoza +1 more
doaj +1 more source
, 2018 We discover new hereditary classes of graphs that are minimal (with respect to set inclusion) of unbounded clique-width. The new examples include split permutation graphs and bichain graphs.
Atminas, A. +3 more
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Small clique number graphs with three trivial critical ideals
Special Matrices, 2018 The critical ideals of a graph are the determinantal ideals of the generalized Laplacian matrix associated to a graph. Previously, they have been used in the understanding and characterizing of the graphs with critical group with few invariant factors ...
Alfaro Carlos A., Valencia Carlos E.
doaj +1 more source
Triangle-free graphs and forbidden subgraphs
Discrete Applied Mathematics, 2002 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
openaire +3 more sources
On bounding the difference of the maximum degree and clique number [PDF]
, 2015 For every k ∈ ℕ0, we consider graphs in which for any induced subgraph, Δ ≤ ω−1+k holds, where Δ is the maximum degree and ω is the maximum clique number of the subgraph. We give a finite forbidden induced subgraph characterization for every k.
Schaudt, Oliver, Weil, Vera
core