摘要
设TX是非空集合X上全变换半群,E是X上非平凡的等价关系,R是X/E的横断面,则TE(X,R)={f∈TX:x,y∈X,(x,y)∈E(f(x),f(y))∈E且f(R)R}是TX的子半群.本文赋予半群TE(X,R)自然偏序关系,通过构造映射的方法,刻画它的左相容元,给出充要条件.
Let TXbe the full transformation semigroup on a nonempty set X,Ebe a nontrivial equivalence relation on Xand Rbe a cross-section of X/E,thenTE(X,R)={f∈TX :x,y∈X,(x,y)∈E(f(x),f(y))∈Eand f(R)R}is a subsemigroup of TX.By constructing suitable mappings,all the left compatible elements were described in the transformation semigroup TE(X,R)endowed with the natural partial order and a necessary and sufficient condition for these elements was given.
引文
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