GREEN'S RELATIONS ON SEMIGROUPS OF REGRESSIVE TRANSFORMATIONS WITH RESTRICTED RANGE
Kritsada Sangkhanan · International Journal of Pure and Apllied Mathematics · 2016
Let X ′ be a subposet of a poset X. Define PRE(X, X ′ ) be the semigroup under composition of all regressive transformations from a subset of X into X ′ .Moreover,In 2012, C. Namnak and E. Laysirikul [3] investigated the Green's relations on TRE(X) = TRE(X, X).Now, we aim to extend the result of them by study the Green's relations on the semigroups TRE(X, X ′ ) and PRE(X, X ′ ).