一个非limit半群簇的limit幺半群簇（英文）

A limit monoid variety which is not a limit semigroup variety

称一个簇是limit簇,如果它是极小的非有限基簇.证明了limit幺半群簇var{A^1×B^1}包含一个非有限基的真子簇,因此var{A^1×B^1}不是limit半群簇,从而给出了一个limit幺半群簇不是limit半群簇的例子.

A limit variety is a variety that is minimal with respect to being non-finitely based.We prove that the limit monoid variety var{A^1×B^1} contains a proper subvariety that is non-finitely based as a semigroup variety,and hence it is not a limit variety of semigroups.This gives an example of limit monoid varieties which is not a limit semigroup variety.