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Related papers: Irreducibility of Arf Numerical Semigroups

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In this paper we give an algorithm for the computation of all the Arf numerical semigroups with a given genus. Moreover, we generalize the concept of genus of a numerical semigroup to good semigroups of $\mathbb{N}^r$ and we give a…

Commutative Algebra · Mathematics 2018-02-09 Giuseppe Zito

A numerical semigroup is irreducible if it cannot be obtained as intersection of two numerical semigroups containing it properly. If we only consider numerical semigroups with the same Frobenius number, that concept is generalized to atomic…

Group Theory · Mathematics 2021-01-27 Aureliano M. Robles-Pérez , José Carlos Rosales

We introduce the notion of pattern for numerical semigroups, which allows us to generalize the definition of Arf numerical semigroups. In this way infinitely many other classes of numerical semigroups are defined giving a classification of…

Rings and Algebras · Mathematics 2019-12-10 Maria Bras-Amorós , Pedro García-Sánchez

In this paper we present the notion of arithmetic variety for numerical semigroups. We study various aspects related to these varieties such as the smallest arithmetic that contains a set of numerical semigroups and we exhibit the root…

Commutative Algebra · Mathematics 2023-11-23 Manuel B. Branco , Ignacio Ojeda , José Carlos Rosales

We investigate numerical semigroups generated by any quadratic sequence with initial term zero and an infinite number of terms. We find an efficient algorithm for calculating the Ap\'ery set, as well as bounds on the elements of the Ap\'ery…

Group Theory · Mathematics 2020-09-07 Mara Hashuga , Megan Herbine , Alathea Jensen

For the elements of a numerical semigroup which are larger than the Frobenius number, we introduce the definition of, seed, by broadening the notion of generator. This new concept allows us to explore the semigroup tree in an alternative…

Combinatorics · Mathematics 2017-12-27 Maria Bras-Amorós , Julio Fernández-González

We present procedures to calculate the set of Arf numerical semigroups with given genus, given conductor and given genus and conductor. We characterize the Kunz coordinates of an Arf numerical semigroup. We also describe Arf numerical…

Commutative Algebra · Mathematics 2016-08-08 P. A. García-Sánchez , B. A. Heredia , H. İ. Karakaş , J. C. Rosales

In this paper we introduce the notion of m-irreducibility that extends the standard concept of irreducibility of a numerical semigroup when the multiplicity is fixed. We analyze the structure of the set of m-irreducible numerical…

Commutative Algebra · Mathematics 2010-06-18 V. Blanco , J. C. Rosales

We study the structure of the family of numerical semigroups with fixed multiplicity and Frobenius number. We give an algorithmic method to compute all the semigroups in this family. As an application we compute the set of all numerical…

Group Theory · Mathematics 2021-12-14 M. B. Branco , I. Ojeda , J. C. Rosales

In this paper we introduce the notion of extension of a numerical semigroup. We provide a characterization of the numerical semigroups whose extensions are all arithmetic and we give an algorithm for the computation of the whole set of…

Commutative Algebra · Mathematics 2020-03-31 Ignacio Ojeda , José Carlos Rosales

We give two algorithmic procedures to compute the whole set of almost symmetric numerical semigroups with fixed Frobenius number and type, and the whole set of almost symmetric numerical semigroups with fixed Frobenius number. Our…

Commutative Algebra · Mathematics 2018-11-16 M. B. Branco , I. Ojeda , J. C. Rosales

Numerical semigroups have been extensively studied throughout the literature, and many of their invariants have been characterized. In this work, we generalize some of the most important results about symmetry, pseudo-symmetry, or…

The pseudo-Frobenius numbers of a numerical semigroup are those gaps of the numerical semigroup that are maximal for the partial order induced by the semigroup. We present a procedure to detect if a given set of integers is the set of…

Commutative Algebra · Mathematics 2019-02-20 M. Delgado , P. A. García-Sánchez , A. M. Robles-Pérez

We provide algorithms for performing computations in generalized numerical semigroups, that is, submonoids of $\mathbb{N}^{d}$ with finite complement in $\mathbb{N}^{d}$. These semigroups are affine semigroups, which in particular implies…

Combinatorics · Mathematics 2019-11-22 Carmelo Cisto , Manuel Delgado , Pedro A. García-Sánchez

We study the so-called atomic GNS, which naturally extends the concept of atomic numerical semigroup. We introduce the notion of corner special gap and we characterize the class of atomic GNS in terms of the cardinality of the set of corner…

Delorme suggested that the set of all complete intersection numerical semigroups can be computed recursively. We have implemented this algorithm, and particularized it to several subfamilies of this class of numerical semigroups: free and…

Combinatorics · Mathematics 2013-01-22 Abdallah Assi , Pedro A. García-Sánchez

An $\mathcal{A}$-semigroup is a numerical semigroup without consecutive small elements. This work generalizes this concept to finite-complement submonoids of an affine cone $\mathcal{C}$. We develop algorithmic procedures to compute all…

Commutative Algebra · Mathematics 2025-06-23 J. C. Rosales , R. Tapia-Ramos , A. Vigneron-Tenorio

We study how certain invariants of numerical semigroups relate to the number of second kind gaps. Furthermore, given two fixed non-negative integers F and k, we provide an algorithm to compute all the numerical semigroups whose Frobenius…

Group Theory · Mathematics 2021-11-16 Aureliano M. Robles-Pérez , José Carlos Rosales

This paper presents a new methodology to count the number of numerical semigroups of given genus or Frobenius number. We apply generating function tools to the bounded polyhedron that classifies the semigroups with given genus (or Frobenius…

Combinatorics · Mathematics 2009-12-23 Victor Blanco , Pedro A. Garcia-Sanchez , Justo Puerto

A numerical semigroup is a co-finite submonoid of the monoid of non-negative integers under addition. Many properties of numerical semigroups rely on some fundamental invariants, such as, among others, the set of gaps (and its cardinality),…

Discrete Mathematics · Computer Science 2025-05-30 Massimo Bartoletti , Stefano Bonzio , Marco Ferrara
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