关于一类变换半群的注记

Note on a Class of Transformation Semigroups

秦美青等人给出E(TE(X;θ))是左零半群、右零半群的充要条件,本文推广了其结论,给出了半群TE(X;θ)的非空子集是左零半群(右零半群)的充要条件。

The sufficient and necessary conditions for E（TE（X;θ）） to be left zero semigroup（right zero semigroup） respectively are given by Qinmeiqing et al.Their conclusions is extended,and given the necessary and sufficient conditions that a nonempty set of semigroup TE（X,θ） is a left zero semigroup（right zero semigroup）.