Abstract (EN):
Let D-n be the pseudovariety of all finite semigroups in which products of length n are right zeros and let D = boolean ORn>1 D-n. It is shown in this paper that, if V is a pseudovariety of semi groups whose global g (V) over bar is finitely based, then V (*) D-n (n greater than or equal to 1) and V (*) D are also finitely based. Moreover, if V is itself finitely based and contains the aperiodic five-element Brandt semigroup, then gV is also finitely based. As a further application, it is proved that the finite basis properties for gV, V (*) D and V (*) D-n (n greater than or equal to 1) are all equivalent for an arbitrary non-group monoidal pseudovariety V.
Language:
English
Type (Professor's evaluation):
Scientific