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Studies in Rings generalised Unique Factorisation Rings

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-47-<br />

theorem 2 0 6 . S<strong>in</strong>ce R has an Art<strong>in</strong>ian quotient r<strong>in</strong>g,<br />

n<br />

CR(O) = o CH 0\) , where Pl,P2'··· 'Pn are t h e d i s t i n c t<br />

i=l<br />

m<strong>in</strong>imal prime ideals of R, so tha t P =<br />

P. for some i ,<br />

1<br />

1 5 i S n. Thu s a f CR(O) 5 C R<br />

(pi) = CR(P) contradict<strong>in</strong>g<br />

the fact tha~ aR = Ra S P.<br />

Remark 2.20.<br />

if'le consid.er a s pecia I case of GUFRs , i.e. GUFRs<br />

wi t h all. height 1 primes are of the form pR == Rp , Then)<br />

by lemma 2.1~each p is a regular element <strong>in</strong> R and so<br />

each pIt = Rp is <strong>in</strong>vertible ( <strong>in</strong> Q(R) ) and thus p € c.<br />

Further it can be seen that, each c E: C can be written as<br />

, uPl ... P n<br />

, [01" some unit u <strong>in</strong> R and for some positive<br />

<strong>in</strong>teger n, and p.s are such that p.R = Rp. is a height 1<br />

1 1 1<br />

prime ideal of R for i = 1,2, •.. ,ne Thus the r<strong>in</strong>g T ,<br />

localised r<strong>in</strong>g of R at C,<br />

co<strong>in</strong>cides with the partial<br />

quotient r<strong>in</strong>g of R with respect to the multiplicative<br />

set generated by the elements p of R such that pR = Rp<br />

is a<br />

height 1 prime.<br />

Theorem 2.21.<br />

Let R be a GUFR and every height one prime ideal<br />

is of the form pR = Rp for some p £ R. Then the follow<strong>in</strong>g<br />

are e qu i va Len t .

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