A SIMPLE HEURISTIC FOR MINIMUM CONNECTED DOMINATING SET IN GRAPHS

2003 ◽  
Vol 14 (02) ◽  
pp. 323-333 ◽  
Author(s):  
PENG-JUN WAN ◽  
KHALED M. ALZOUBI ◽  
OPHIR FRIEDER

Let α2(G), γ(G) and γc(G) be the 2-independence number, the domination number, and the connected domination number of a graph G respectively. Then α2(G) ≤ γ (G) ≤ γc(G). In this paper , we present a simple heuristic for Minimum Connected Dominating Set in graphs. When running on a graph G excluding Km (the complete graph of order m) as a minor, the heuristic produces a connected dominating set of cardinality at most 7α2(G) - 4 if m = 3, or at most [Formula: see text] if m ≥ 4. In particular, if running on a planar graph G, the heuristic outputs a connected dominating set of cardinality at most 15α2(G) - 5.

2018 ◽  
Vol 7 (4.10) ◽  
pp. 585 ◽  
Author(s):  
Annie Jasmine.S.E ◽  
K. Ameenal Bibi

Let D be the minimum connected dominating set of a jump graph . If  of  contains a connected dominating set , then  is called the inverse connected dominating set of the jump graph . The minimum cardinality of an inverse connected dominating set is the inverse connected domination number of the jump graph, denoted by. The disjoint connected domination number, of the jump graph , is the minimum cardinality of the union of two disjoint connected dominating set of  . In this paper we have established bounds, exact values of and graph theoretic relations between the inverse connected domination number of the jump graph with other parameters of G.       


2020 ◽  
Vol 12 (05) ◽  
pp. 2050066
Author(s):  
Enrico L. Enriquez ◽  
Albert D. Ngujo

Let [Formula: see text] be a connected simple graph. A set [Formula: see text] is a doubly connected dominating set if it is dominating and both [Formula: see text] and [Formula: see text] are connected. A nonempty subset [Formula: see text] of the vertex set [Formula: see text] is a clique in [Formula: see text] if the graph [Formula: see text] induced by [Formula: see text] is complete. A clique dominating set [Formula: see text] of [Formula: see text] is a clique doubly connected dominating set if [Formula: see text] is a doubly connected dominating set of [Formula: see text]. The clique doubly connected domination number of [Formula: see text], denoted by [Formula: see text], is the smallest cardinality of a clique doubly connected dominating set [Formula: see text] of [Formula: see text]. In this paper, we give the characterization of the clique doubly connected dominating set and the clique doubly connected domination number in the join (and lexicographic product) of two graphs.


2006 ◽  
Vol 4 (1) ◽  
pp. 34-45 ◽  
Author(s):  
Joanna Cyman ◽  
Magdalena Lemańska ◽  
Joanna Raczek

AbstractFor a given connected graph G = (V, E), a set $$D \subseteq V(G)$$ is a doubly connected dominating set if it is dominating and both 〈D〉 and 〈V (G)-D〉 are connected. The cardinality of the minimum doubly connected dominating set in G is the doubly connected domination number. We investigate several properties of doubly connected dominating sets and give some bounds on the doubly connected domination number.


2012 ◽  
Vol 11 (4) ◽  
pp. 91-98 ◽  
Author(s):  
Mahadevan G ◽  
A Selvam Avadayappan ◽  
Twinkle Johns

A subset S of vertices in a graph G = (V,E) is a dominating set if every vertex in V-S is adjacent to atleast one vertex in S. A dominating set S of a connected graph G is called a connected dominating set if the induced sub graph < S > is connected. A set S is called a global dominating set of G if S is a dominating set of both G and . A subset S of vertices of a graph G is called a global connected dominating set if S is both a global dominating and a connected dominating set. The global connected domination number is the minimum cardinality of a global connected dominating set of G and is denoted by γgc(G). In this paper we characterize the classes of graphs for which γgc(G) + χ(G) = 2n-5 and 2n-6 of global connected domination number and chromatic number and characterize the corresponding extremal graphs.


Author(s):  
Rana Khoeilar ◽  
Hossein Karami ◽  
Mustapha Chellali ◽  
Seyed Mahmoud Sheikholeslami ◽  
Lutz Volkmann

A dominating set of $G=(V,E)$ is a subset $S$ of $V$ such that every vertex in $V-S$ has at least one neighbor in $S.$ A connected dominating set of $G$ is a dominating set whose induced subgraph is connected. The minimum cardinality of a connected dominating set is the connected domination number $\gamma _{c}(G)$. Let $\delta ^{\ast }(G)=\min \{\delta (G),\delta (% \overline{G})\}$, where $\overline{G}$ is the complement of $G$ and $\delta (G)$ is the minimum vertex degree. In this paper, we improve upon existing results by providing new Nordhaus-Gaddum type results for connected domination. In particular, we show that if $G$ and $\overline{G}$ are both connected and $\min \{\gamma _{c}(G),\gamma _{c}(\overline{G})\}\geq 3$, then $\gamma _{c}(G)+\gamma _{c}(\overline{G})\leq 4+(\delta ^{\ast }(G)-1)(% \frac{1}{\gamma _{c}(G)-2}+\frac{1}{\gamma _{c}(\overline{G})-2})$ and $% \gamma _{c}(G)\gamma _{c}(\overline{G})\leq 2(\delta ^{\ast }(G)-1)(\frac{1}{% \gamma _{c}(G)-2}+\frac{1}{\gamma _{c}(\overline{G})-2}+\frac{1}{2})+4$. Moreover, we will establish accordingly results for total domination.


2013 ◽  
Vol 05 (03) ◽  
pp. 1350009
Author(s):  
O. FAVARON ◽  
R. KHOEILAR ◽  
S. M. SHEIKHOLESLAMI

A set S of vertices of a graph G is a total outer-connected dominating set if every vertex in V(G) is adjacent to some vertex in S and the subgraph G[V\S] induced by V\S is connected. The total outer-connected domination numberγ toc (G) is the minimum size of such a set. The total outer-connected domination subdivision number sd γ toc (G) is the minimum number of edges that must be subdivided in order to increase the total outer-connected domination number. We prove the existence of sd γ toc (G) for every connected graph G of order at least 3 and give upper bounds on it in some classes of graphs.


2014 ◽  
Vol 06 (03) ◽  
pp. 1450032
Author(s):  
Shipeng Wang ◽  
Baoyindureng Wu ◽  
Xinhui An ◽  
Xiaoping Liu ◽  
Xingchao Deng

A set S of vertices of a graph G is an outer-connected dominating set if every vertex not in S is adjacent to some vertex in S and the subgraph induced by V\S is connected. The outer-connected domination number [Formula: see text] is the minimum size of such a set. We present an infinite family of 2-connected cubic graphs, in which the number of vertices in a longest path are much less than the half of their orders. This disprove a recent conjecture posed by Akhbari, Hasni, Favaron, Karami, Sheikholeslami.


Sign in / Sign up

Export Citation Format

Share Document