SOME RESULTS ON 1-MOVABLE RESTRAINED PERFECT DOMINATING SETS IN THE JOIN AND CORONA OF GRAPHS

A nonempty subset S of V(G) is a 1-movable restrained perfect dominating set of G if S = V(G) or S subset of V(G) is a restrained perfect dominating set of G and for every v is an element of S, there exists u is an element of (V(G)\S) boolean AND NG(v) such that (S\{v}) ? {u} is a restrained perfect dominating set of G. The smallest cardinality of a 1-movable restrained perfect dominating set of G is called 1-movable restrained perfect domination number of G, denoted by gamma 1mrp(G). A 1-movable restrained perfect dominating set of G of cardinality gamma 1mrp(G) is called a gamma m1rp-set of G. This paper characterizes 1-movable restrained perfect dominating sets in the join and corona of two connected graphs.