Price of Independence for the Dominating Set Problem
نویسنده
چکیده
Let γ(G) and ι(G) be the domination and independent domination numbers of a graph G, respectively. In this paper, we define the Price of Independence of a graph G as the ratio ι(G) γ(G) . Firstly, we bound the Price of Independence by values depending on the number of vertices. Secondly, we consider the question of computing the Price of Independence of a given graph. Unfortunately, the decision version of this question is Θp2-complete. The class Θ p 2 is the class of decision problems solvable in polynomial time, for which we can make O(log(n)) queries to an NP-oracle. Finally, we restore the true characterization of domination perfect gaphs, i.e. graphs whose the Price of Independence is always 1 for all induced subgraphs, and we propose a conjecture on futher problems. keywords : domination, independent domination, forbidden induced subgraphs, computational complexity. MSC : 05C69, 05C75.
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