Resumen de Universal formulae of Euler-Fermat type for subsets of Zm

Stefan Schwarz

• In several papers Paul Dubreil has studied the multiplicative semigroup of several types of rings and conditions for semigroups which can serve as an underlying semigroup of a ring. In this paper we shall deal with the multiplicative semigroup of $Z_m$, which will be denoted by $S(m)$, and we shall treat a rather unconventional problem concerning the powers of a subset of $S(m)$.