Studies in Rings generalised Unique Factorisation Rings
Studies in Rings generalised Unique Factorisation Rings
Studies in Rings generalised Unique Factorisation Rings
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-38-<br />
Let R be a GUFR with over-r<strong>in</strong>g S. We shall make<br />
use of a certa<strong>in</strong> p a r t i a I quo t i en t r<strong>in</strong>g of R. Let<br />
C =[a€ R/aR = Ra is S-<strong>in</strong>vertjble}. We prove C consists<br />
of regular elements and C is a<br />
(right and left) Ore set.<br />
QUOTIENT RINGS<br />
Theorem 2 0 6 .<br />
Let R be a GUFR with the over-r<strong>in</strong>g S. Then C<br />
conta<strong>in</strong>s only regulor elements and C is an Ore set.<br />
Proof<br />
Let a E: C, we provelR( a) = r R( a) = o. S<strong>in</strong>c e<br />
a f e, aR = Ra is S-<strong>in</strong>vertible and so there exists an<br />
R-subbimodule 1- 1 of 5 such that (aR)1- 1 = 1- 1(aR) = R.<br />
Thus we can f<strong>in</strong>d elements r i<br />
c R, si ( 1- l f 5 for<br />
i=1,2, •.. ,n, such that<br />
which implies<br />
n<br />
n<br />
L (ar.)s. = 1. iAe<br />
1=<br />
· 1 1 1<br />
n<br />
a l: r.s.=l<br />
· 1 l 1.<br />
fS(a E r.s.) = lS(l)=O and consequently<br />
. 11.1<br />
1=<br />
n<br />
1=<br />
lR (a) ~<br />
r R<br />
(a) = o.<br />
~ (a)<br />
< ls( a L r.s.) = I S<br />
( l ) = o. Similarly<br />
- · 111<br />
1=<br />
For the second part of the theorem, let a,b e C,<br />
then aR=Ra and bR = Rb. Now abR = a(Rb) = Rabo S<strong>in</strong>ce