Connected Domination Number of Central Trees

Let G = (V, E) be a graph. A subset S of V is called a dominating set of G if every vertex not in S is adjacent to some vertex in S. ##The domination number γ(G) of G is the minimum cardinality taken over all dominating sets of G. A dominating set S is called a connected dominating set if the induced subgraph S is connected. ##The minimum cardinality taken over all connected dominating sets of G is called the connected domination number of G and is denoted by γc (G). ##In this paper, we study the connected domination number of central trees. Indeed, we obtain some tight bounds for the connected domination number of a central trees C(T) in terms of some invariants of the graph T.## Also we characterize the connected domination number of the central of some families of trees