The unit sum number of Baer rings

Document Type : Other


1 Semnan UniversityFaculty of Mathematics, Statistics and Computer Science, Semnan University, Semnan, Iran.

2 Faculty of Mathematics, Statistics and Computer Science, Semnan University, Semnan, Iran.


In this paper we prove that each element of any regular Baer ring is a sum of two units if no factor ring of $R$ is isomorphic
to $Z_2$ and we characterize regular Baer rings with unit sum numbers $\omega$ and $\infty$. Then as an application, we discuss the unit  sum number of some classes of group rings.


Main Subjects

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