The unit sum number of discrete modules

Document Type : Research Paper



In this paper, we show that every element of a discrete module is a
sum of two units if and only if its endomorphism ring has no
factor ring isomorphic to $Z_{2}$. We also characterize unit sum
number equal to two for the endomorphism ring of quasi-discrete
modules with finite exchange property.


Volume 37, No. 4
December 2011
Pages 243-249
  • Receive Date: 19 April 2010
  • Revise Date: 27 July 2010
  • Accept Date: 27 July 2010
  • First Publish Date: 15 December 2011