Displaying 21 – 40 of 169

Showing per page

Birings and plethories of integer-valued polynomials

Jesse Elliott (2010)

Actes des rencontres du CIRM

Let A and B be commutative rings with identity. An A - B -biring is an A -algebra S together with a lift of the functor Hom A ( S , - ) from A -algebras to sets to a functor from A -algebras to B -algebras. An A -plethory is a monoid object in the monoidal category, equipped with the composition product, of A - A -birings. The polynomial ring A [ X ] is an initial object in the category of such structures. The D -algebra Int ( D ) has such a structure if D = A is a domain such that the natural D -algebra homomorphism θ n : D i = 1 n Int ( D ) Int ( D n ) is an isomorphism for...

Cale Bases in Algebraic Orders

Martine Picavet-L’Hermitte (2003)

Annales mathématiques Blaise Pascal

Let R be a non-maximal order in a finite algebraic number field with integral closure R ¯ . Although R is not a unique factorization domain, we obtain a positive integer N and a family 𝒬 (called a Cale basis) of primary irreducible elements of R such that x N has a unique factorization into elements of 𝒬 for each x R coprime with the conductor of R . Moreover, this property holds for each nonzero x R when the natural map Spec ( R ¯ ) Spec ( R ) is bijective. This last condition is actually equivalent to several properties linked...

Construction of p o -groups with quasi-divisors theory

Jiří Močkoř (2000)

Czechoslovak Mathematical Journal

A method is presented making it possible to construct p o -groups with a strong theory of quasi-divisors of finite character and with some prescribed properties as subgroups of restricted Hahn groups H ( Δ , ) , where Δ are finitely atomic root systems. Some examples of these constructions are presented.

Décomposition du Galois-module des entiers d'une extension cyclique de degré premier d'un corps de nombres ou d'un corps local

Françoise Bertrandias (1979)

Annales de l'institut Fourier

Soit A un anneau de Dedekind, de corps des fractions K , et soit L une extension galoisienne de K , dont le groupe de Galois G est cyclique d’ordre premier. On note B la clôture intégrale de A dans L . Il existe une unique décomposition du A [ G ] -module B en somme directe de sous-modules indécomposables. On détermine cette décomposition lorsque K est un corps local ou un corps de nombres. Le résultat dépend d’une part des caractères irréductibles de G sur K , d’autre part des nombres de ramification associés...

Determining Integer-Valued Polynomials From Their Image

Vadim Ponomarenko (2010)

Actes des rencontres du CIRM

This note summarizes a presentation made at the Third International Meeting on Integer Valued Polynomials and Problems in Commutative Algebra. All the work behind it is joint with Scott T. Chapman, and will appear in [2]. Let Int ( ) represent the ring of polynomials with rational coefficients which are integer-valued at integers. We determine criteria for two such polynomials to have the same image set on .

Differences in sets of lengths of Krull monoids with finite class group

Wolfgang A. Schmid (2005)

Journal de Théorie des Nombres de Bordeaux

Let H be a Krull monoid with finite class group where every class contains some prime divisor. It is known that every set of lengths is an almost arithmetical multiprogression. We investigate which integers occur as differences of these progressions. In particular, we obtain upper bounds for the size of these differences. Then, we apply these results to show that, apart from one known exception, two elementary p -groups have the same system of sets of lengths if and only if they are isomorphic.

Currently displaying 21 – 40 of 169