n-Clean Rings
n-Clean Rings
复制标题
DOI:
10.1142/s1005386706000538
复制
发表时间:
2006-12
影响因子:
0.3
通讯作者:
Guangshi Xiao;W. Tong
中科院分区:
文献类型:
--
作者:
Guangshi Xiao;W. Tong
Let n be a positive integer. A ring R is called n-clean if every element of R can be written as a sum of an idempotent and n units in R. The class of n-clean rings contains clean rings and (S,n)-rings (i.e., every element is a sum of no more than n units). In this paper, we investigate some properties on n-clean rings. There exists a clean and (S,3)-ring which is not an (S,2)-ring. If R is a ring satisfying (SI), then the polynomial ring R[x] is not n-clean for any positive integer n. An example shows that for any positive integer n> 1, there exists a non n-clean ring R such that the 2× 2 matrix ring M2(R) over R is n-clean.