Characterizations of Inversely S-Invariant Elements in Semigroups of Full Transformations as Magnifying Elements

A. In this paper, for any subsemigroup S of the full transformation semigroup T (X), we introduce the notions of inversely left-S-invariant and inversely right-S-invariant elements of S. Our main aims are to give characterizations for inversely left-S-invariant and inversely right-S-invariant elements of S to be left and right magnifying, respectively.Moreover, we apply our results to characterize left and right magnifying elements in several well-known subsemigroups of T (X).