Ken-ichi Kawarabayashi (2004)
Discussiones Mathematicae Graph Theory
Similarity:
Let G be a graph of order n. Let K¯ₗ be the graph obtained from Kₗ by removing one edge. In this paper, we propose the following conjecture: Let G be a graph of order n ≥ lk with δ(G) ≥ (n-k+1)(l-3)/(l-2)+k-1. Then G has k vertex-disjoint K¯ₗ. This conjecture is motivated by Hajnal and Szemerédi's [6] famous theorem. In this paper, we verify this conjecture for l=4.
Wyatt J. Desormeaux, Teresa W. Haynes, Michael A. Henning (2018)
Discussiones Mathematicae Graph Theory
Similarity:
A dominating set in a graph G is a set S of vertices such that every vertex in V (G) S is adjacent to at least one vertex in S, and the domination number of G is the minimum cardinality of a dominating set of G. Placing constraints on a dominating set yields different domination parameters, including total, connected, restrained, and clique domination numbers. In this paper, we study relationships among domination parameters of a graph and its complement.
Bostjan Bresar (2001)
Discussiones Mathematicae Graph Theory
Similarity:
A dominating set D for a graph G is a subset of V(G) such that any vertex in V(G)-D has a neighbor in D, and a domination number γ(G) is the size of a minimum dominating set for G. For the Cartesian product G ⃞ H Vizing's conjecture [10] states that γ(G ⃞ H) ≥ γ(G)γ(H) for every pair of graphs G,H. In this paper we introduce a new concept which extends the ordinary domination of graphs, and prove that the conjecture holds when γ(G) = γ(H) = 3.
DeLaViña, Ermelinda, Waller, Bill (2008)
The Electronic Journal of Combinatorics [electronic only]
Similarity:
Evdokimov, S.A., Ponomarenko, I.N. (2004)
Zapiski Nauchnykh Seminarov POMI
Similarity:
Marietjie Frick, Frank Bullock (2001)
Discussiones Mathematicae Graph Theory
Similarity:
The nth detour chromatic number, χₙ(G) of a graph G is the minimum number of colours required to colour the vertices of G such that no path with more than n vertices is monocoloured. The number of vertices in a longest path of G is denoted by τ( G). We conjecture that χₙ(G) ≤ ⎡(τ(G))/n⎤ for every graph G and every n ≥ 1 and we prove results that support the conjecture. We also present some sufficient conditions for a graph to have nth chromatic number at most 2.
Brešar, Boštjan (2005)
The Electronic Journal of Combinatorics [electronic only]
Similarity:
Robert R. Rubalcaba, Peter J. Slater (2007)
Discussiones Mathematicae Graph Theory
Similarity:
A dominating set S of a graph G is called efficient if |N[v]∩ S| = 1 for every vertex v ∈ V(G). That is, a dominating set S is efficient if and only if every vertex is dominated exactly once. In this paper, we investigate efficient multiple domination. There are several types of multiple domination defined in the literature: k-tuple domination, {k}-domination, and k-domination. We investigate efficient versions of the first two as well as a new type of multiple domination.
Ville Junnila (2015)
Discussiones Mathematicae Graph Theory
Similarity:
A set C of vertices in a graph G = (V,E) is total dominating in G if all vertices of V are adjacent to a vertex of C. Furthermore, if a total dominating set C in G has the additional property that for any distinct vertices u, v ∈ V C the subsets formed by the vertices of C respectively adjacent to u and v are different, then we say that C is a locating-total dominating set in G. Previously, locating-total dominating sets in strips have been studied by Henning and Jafari Rad (2012)....
Hansberg, Adriana, Meierling, Dirk, Volkmann, Lutz (2007)
The Electronic Journal of Combinatorics [electronic only]
Similarity:
Michael A. Henning, Alister J. Marcon (2016)
Discussiones Mathematicae Graph Theory
Similarity:
Let G be a graph with no isolated vertex. In this paper, we study a parameter that is squeezed between arguably the two most important domination parameters; namely, the domination number, γ(G), and the total domination number, γt(G). A set S of vertices in a graph G is a semitotal dominating set of G if it is a dominating set of G and every vertex in S is within distance 2 of another vertex of S. The semitotal domination number, γt2(G), is the minimum cardinality of a semitotal dominating...
Wilfried Imrich, Blaz Zmazek, Janez Zerovnik (2003)
Discussiones Mathematicae Graph Theory
Similarity:
By Ulam's conjecture every finite graph G can be reconstructed from its deck of vertex deleted subgraphs. The conjecture is still open, but many special cases have been settled. In particular, one can reconstruct Cartesian products. We consider the case of k-vertex deleted subgraphs of Cartesian products, and prove that one can decide whether a graph H is a k-vertex deleted subgraph of a Cartesian product G with at least k+1 prime factors on at least k+1 vertices each, and that H uniquely...
Abdollah Alimadadi, Doost Ali Mojdeh, Nader Jafari Rad (2016)
Discussiones Mathematicae Graph Theory
Similarity:
Let G = (V,E) be a graph. A set S ⊆ V is a dominating set if Uv∈S N[v] = V , where N[v] is the closed neighborhood of v. Let L ⊆ V be a dominating set, and let v be a designated vertex in V (an intruder vertex). Each vertex in L ∩ N[v] can report that v is the location of the intruder, but (at most) one x ∈ L ∩ N[v] can report any w ∈ N[x] as the intruder location or x can indicate that there is no intruder in N[x]. A dominating set L is called a liar’s dominating set if every v ∈ V...
Bert Hartnell, Douglas F. Rall (1995)
Discussiones Mathematicae Graph Theory
Similarity:
The domination number of a graph G is the smallest order, γ(G), of a dominating set for G. A conjecture of V. G. Vizing [5] states that for every pair of graphs G and H, γ(G☐H) ≥ γ(G)γ(H), where G☐H denotes the Cartesian product of G and H. We show that if the vertex set of G can be partitioned in a certain way then the above inequality holds for every graph H. The class of graphs G which have this type of partitioning includes those whose 2-packing number is no smaller than γ(G)-1 as...
Kostochka, A.V. (1990)
Mathematica Pannonica
Similarity:
Wayne Goddard, Teresa Haynes, Debra Knisley (2004)
Discussiones Mathematicae Graph Theory
Similarity:
For a graphical property P and a graph G, we say that a subset S of the vertices of G is a P-set if the subgraph induced by S has the property P. Then the P-domination number of G is the minimum cardinality of a dominating P-set and the P-independence number the maximum cardinality of a P-set. We show that several properties of domination, independent domination and acyclic domination hold for arbitrary properties P that are closed under disjoint unions and subgraphs.
John Georges, Jianwei Lin, David Mauro (2014)
Discussiones Mathematicae Graph Theory
Similarity:
Let K3n denote the Cartesian product Kn□Kn□Kn, where Kn is the complete graph on n vertices. We show that the domination number of K3n is [...]
A.P. Santhakumaran, P. Titus (2012)
Discussiones Mathematicae Graph Theory
Similarity:
For a connected graph G of order p ≥ 2 and a vertex x of G, a set S ⊆ V(G) is an x-monophonic set of G if each vertex v ∈ V(G) lies on an x -y monophonic path for some element y in S. The minimum cardinality of an x-monophonic set of G is defined as the x-monophonic number of G, denoted by mₓ(G). An x-monophonic set of cardinality mₓ(G) is called a mₓ-set of G. We determine bounds for it and characterize graphs which realize these bounds. A connected graph of order p with vertex monophonic...