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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-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>,