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Viewing Version 2 of 'ideal inverting in Pr\"ufer ring'
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Title of object: ideal inverting in Pr\"ufer ring
Canonical Name: IdealInvertingInPruferRing
Type: Definition

Created on: 2004-08-15 15:24:55
Modified on: 2004-08-15 15:32:59

Creator: pahio
Modifier: pahio
Author: pahio

Classification: msc:13C13

Preamble:

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%\usepackage{psfrag}
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Content:

\textbf{Theorem.} \,Let $\mathfrak{a}_1$, ..., $\mathfrak{a}_n$ be invertible fractional ideals of a Pr\"ufer ring. \,Then also their sum and intersection are invertible, and the inverse ideals of these are obtained by the formulae resembling de Morgan's laws:
(\mathfrak{a}_1+...+\mathfrak{a}_n)^{-1} = \mathfrak{a}_1^{-1}\cap...\cap\mathfrak{a}_n^{-1}
(\mathfrak{a}_1\cap...\cap\mathfrak{a}_n)^{-1} = \mathfrak{a}_1^{-1}+...+\mathfrak{a}_n^{-1}
$$