A total dominating set of a graph G is a set D of vertices of G such that every vertex of G has a neighbor in D. The total domination number of a graph G, denoted by γt(G), is the minimum cardinality of a total dominating set of G. Chellali and Haynes [Total and paired-domination numbers of a tree, AKCE International Journal of Graphs and Combinatorics 1 (2004), 69– 75] established the followin...

A set S ⊆ V of vertices in a graph G = (V,E) without isolated vertices is a total dominating set if every vertex of V is adjacent to some vertex in S. The total domination number γt(G) is the minimum cardinality of a total dominating set of G. The total domination subdivision number sdγt(G) is the minimum number of edges that must be subdivided (each edge in G can be subdivided at most once) in...

A total dominating set of a graph is a set of vertices such that every vertex is adjacent to a vertex in the set. We show that given a graph of order n with minimum degree at least 2, one can add at most (n−2√n )/4+O(log n) edges such that the resulting graph has two disjoint total dominating sets, and this bound is best possible.

A subset S of vertices in a graph G is a global total dominating set, or just GTDS, if S is a total dominating set of both G and G. The global total domination number γgt(G) of G is the minimum cardinality of a GTDS of G. In this paper, we show that the decision problem for γgt(G) is NP-complete, and then characterize graphs G of order n with γgt(G) = n− 1.

In this paper, the concept of a strong n-Connected Total Perfect k-connected total perfect k-dominating set and weak n-connected in fuzzy graphs is introduced. current work, triple-connected dominating modified to an nctpkD(G) number γnctpD(G). New definitions are compared with old ones. Strong obtained. The results those sets discussed spanning graphs, arcs, sets, generalization complete, conn...

Given a graph $$G=(V,E)$$ and an integer k, the Minimum Membership Dominating Set (MMDS) problem seeks to find dominating set $$S \subseteq V$$ of G such that for each $$v \in , $$\vert N[v] \cap S\vert $$ is at most k. We investigate parameterized complexity obtain following results MMDS problem. First, we show NP-hard even on planar bipartite graphs. Next, W[1]-hard parameter pathwidth (and t...