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Un anneau de Prüfer

H. Lombardi (2010)

Actes des rencontres du CIRM

Let E be the ring of integer valued polynomials over . This ring is known to be a Prüfer domain. But it seems there does not exist an algorithm for inverting a nonzero finitely generated ideal of E . In this note we show how to obtain such an algorithm by deciphering a classical abstract proof that uses localisations of E at all prime ideals of E . This confirms a general program of deciphering abstract classical proofs in order to obtain algorithmic proofs.

Uppers to zero in R [ x ] and almost principal ideals

Keivan Borna, Abolfazl Mohajer-Naser (2013)

Czechoslovak Mathematical Journal

Let R be an integral domain with quotient field K and f ( x ) a polynomial of positive degree in K [ x ] . In this paper we develop a method for studying almost principal uppers to zero ideals. More precisely, we prove that uppers to zero divisorial ideals of the form I = f ( x ) K [ x ] R [ x ] are almost principal in the following two cases: – J , the ideal generated by the leading coefficients of I , satisfies J - 1 = R . – I - 1 as the R [ x ] -submodule of K ( x ) is of finite type. Furthermore we prove that for I = f ( x ) K [ x ] R [ x ] we have: – I - 1 K [ x ] = ( I : K ( x ) I ) . – If there exists p / q I - 1 - K [ x ] , then ( q , f ) 1 ...

When spectra of lattices of z -ideals are Stone-Čech compactifications

Themba Dube (2017)

Mathematica Bohemica

Let X be a completely regular Hausdorff space and, as usual, let C ( X ) denote the ring of real-valued continuous functions on X . The lattice of z -ideals of C ( X ) has been shown by Martínez and Zenk (2005) to be a frame. We show that the spectrum of this lattice is (homeomorphic to) β X precisely when X is a P -space. This we actually show to be true not only in spaces, but in locales as well. Recall that an ideal of a commutative ring is called a d -ideal if whenever two elements have the same annihilator and...

z⁰-Ideals and some special commutative rings

Karim Samei (2006)

Fundamenta Mathematicae

In a commutative ring R, an ideal I consisting entirely of zero divisors is called a torsion ideal, and an ideal is called a z⁰-ideal if I is torsion and for each a ∈ I the intersection of all minimal prime ideals containing a is contained in I. We prove that in large classes of rings, say R, the following results hold: every z-ideal is a z⁰-ideal if and only if every element of R is either a zero divisor or a unit, if and only if every maximal ideal in R (in general, every prime z-ideal) is a z⁰-ideal,...

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