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On Rees weakly projective right acts


In this article, we present an extension of the concept of weakly projective acts to the socalled (S/I, S/J)-projective acts. Retracts, coproducts, and products of acts as well as Rees factor acts are considered from the point of view of these properties. They are used to describe monoids that are disjoint unions of a group with a left zero semigroup or with a disjoint union of simple right ideals. We suggest concepts of weak QF-monoids.

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Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 10, No. 3, pp. 85–96, 2004.

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Knauer, U., Oltmanns, H. On Rees weakly projective right acts. J Math Sci 139, 6715–6722 (2006).

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  • Disjoint Union
  • Simple Semigroup
  • Left Zero
  • Zero Semigroup
  • Left Zero Semigroup