On orders of directly indecomposable finite rings
1992 ◽
Vol 46
(3)
◽
pp. 353-359
◽
Keyword(s):
Let R be a directly indecomposable finite ring. Let p be a prime, let m be a positive integer and suppose the radical of R has pm elements. Then we show that . As a consequence, we have that, for a given finite nilpotent ring N, there are up to isomorphism only finitely many finite rings not having simple ring direct summands, with radical isomorphic to N. Let R* denote the group of units of R. Then we prove that (1 − 1/p)m+1 ≤ |R*| / |R| ≤ 1 − 1/pm. As a corollary, we obtain that if R is a directly indecomposable non-simple finite 2′-ring then |R| < |R*| |Rad(R)|.
2005 ◽
Vol 2005
(4)
◽
pp. 579-592
Keyword(s):
1976 ◽
Vol 28
(1)
◽
pp. 94-103
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2009 ◽
Vol 79
(2)
◽
pp. 177-182
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2002 ◽
Vol 170
(2-3)
◽
pp. 175-183
◽
2011 ◽
Vol 54
(1)
◽
pp. 193-199
◽
Keyword(s):
1991 ◽
Vol 44
(3)
◽
pp. 353-355
◽