摘要
对任一个非空集X,X上的全变换半群T(X)的一个子幺半群M被称为半传递,如果M为非传递,且对每个序对(x,y)∈X×X,存在∈M使x=y或y=x.本文刻画了全变换半群T(X)的所有极大半传递子幺半群;对T(X)的每个极大半传递子幺半群M,相关秩r(T(X),M)被证明为1.对有限集X,给出T(X)的极大半传递子幺半群的个数,且T(X)的最大基数的半传递子幺半群被刻画.
For an arbitrary non-empty set X, a submonoid M of the semigroup T(X) of full transformations on X is said to be half-transitive provided that it is intransitive, and for every ordered pair (x,y) ∈ X ×X there is some φ∈M such that either xφ = y or yφ = x. In this paper all maximal half-transitive submonoids of T(X) ave described. The relative rank r(T(X), M) is shown to be 1 for every maximal half-transitive submonoid M of T(X). For a finite set X, the number of maximal half-transitive submonoids of T(X) is counted, and the largest half-transitive submonoids of T(X) are described.
出处
《数学进展》
CSCD
北大核心
2011年第5期580-586,共7页
Advances in Mathematics(China)
基金
supported by NSFC(No.10971086)
关键词
半群
全变换:半传递幺半群:相关秩
semigroup
full transiormations
hall-transitive monoid
relative rank