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Studies in Rings generalised Unique Factorisation Rings

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-40-<br />

P.O C = ~ for i = 1 , 2 , ... , n·. Then P.Ts are prime<br />

1 ).<br />

ideals of T for i=1,2, ... ,ne Let J be an ideal of T<br />

such that P.T < J for each i = 1,2, ... ,n. Then<br />

~<br />

p. T n R < J n R = I for 1 ~ i ~ n ,<br />

1<br />

be the .mi.ni rna I primes over I.<br />

Then it is obvious<br />

that P. f P.! for i = 1,2, ... ,11, j = 1,2, •.. ,m and<br />

). J<br />

thus each P.' conta<strong>in</strong>s elements of Co Therefore the<br />

J<br />

product Pl'P2' ...P m'<br />

also conta<strong>in</strong>s elements of C. But<br />

Pl'P2' •.•P m<br />

' S I, consequently I conta<strong>in</strong>s an element C,<br />

i.e., I conta<strong>in</strong>s a unit of T. Also 'vve have IT = (J n R)T S J.<br />

Hence J conta<strong>in</strong>s a unit of T. Thus J = T and we proved<br />

that PIT, P 2T,<br />

... ,PnT are maximal ideals of T.<br />

Further, if M is any maximal ideal, then M = P.T<br />

1<br />

for some i = 1,2, •.• ,n. For, if M ~ P.T for all<br />

1<br />

i = 1,2, •.. ,n .<br />

i<br />

= 1,2, •.. ,n.<br />

.Then Mn R is not conta<strong>in</strong>ed <strong>in</strong> ·P. for any<br />

1<br />

Thus, as above,<br />

it can be seen that<br />

(~,nR)nc 1= y1, which implies that M conta<strong>in</strong>s a unit of T,<br />

contradict<strong>in</strong>g the maximality of M.This completes the proof.<br />

In an NUFR,<br />

the m<strong>in</strong>imal prime ideal not conta<strong>in</strong><strong>in</strong>g<br />

a normal Q(R)-<strong>in</strong>vertible ideal is 0, and so, OT = 0 is<br />

a ma x i ma 1 i ciea 1 0 f ToTh U 5 we 0 b t a <strong>in</strong>,

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