On the Group of Units of Z[A4] PDF

Keywords

integrals, Z-basis, units

Abstract

The group of units of the integral group ring Z[A4] has been determined by Allen, P.J. and Hobby, C. In this note we use a different method to give a description of it, namely we consider Z[A4] as a module over the ring of integer Z. Since Z[A4] has a finite rank which is |A4|, therefore we construct a Z-basis for it and we use this basis to described Z[A4] and Characterize its group of units.