In [16] Nowakowski and Rall listed a series of conjectures involving several different graph products. particular, they conjectured that $$i(G\times H) \ge i(G)i(H)$$ where i(G) is the independent domination number G $$G\times H$$ direct product graphs H. We show this conjecture false, and, in fact, construct pairs for which $$\min \{i(G), i(H)\} - i(G\times H)$$ arbitrarily large. also give ex...

In this article we give a new definition of direct product of two arbitrary fuzzy graphs. We define the concepts of domination and total domination in this new product graph. We obtain an upper bound for the total domination number of the product fuzzy graph. Further we define the concept of total α-domination number and derive a lower bound for the total domination number of the product fuzzy ...

In this note the split domination number of the Cartesian product of two paths is considered. Our results are related to [2] where the domination number of Pm¤Pn was studied. The split domination number of P2¤Pn is calculated, and we give good estimates for the split domination number of Pm¤Pn expressed in terms of its domination number.

The independent domination number of a graph G, denoted i(G), is the minimum cardinality of a maximal independent set of G. A maximal independent set of cardinality i(G) in G we call an i(G)-set. In this paper we provide a constructive characterization of trees G that have two disjoint i(G)-sets. © 2005 Elsevier B.V. All rights reserved.