Sequationally compact S-acts

چکیده مقاله

The investigation of equational compactness was ini-
tiated by Banaschewski and Nelson. They proved that pure in-
jectivity is equivalent to equational compactness. Here, we de ne
the so-called sequentially compact acts over semigroups and study
some of their categorical and homological properties. Some Baer
conditions for injectivity are also presented.