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How large can the domination numbers of a graph be?

A vertex v in a graph G dominates itself as well as its neighbors. A set S of vertices in G is (1) a dominating set if every vertex of G is dominated by some vertex of S, (2) an open dominating set if every vertex of G is dominated by a vertex of S distinct from itself, and (3) a double dominating set if every vertex of G is dominated by at least two distinct vertices of S. The minimum cardinality of a set S satisfying (1), (2), and (3), respectively, is the domination number, open domination number, and double domination number of G, respectively. We consider the problem of determining the maximum value of each of these domination numbers among all graphs of a given order and size.