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Let $S=K[x_1, \ldots,x_n]$ denote the polynomial ring in $n$ variables over a field $K$ and $I \subset S$ a monomial ideal. Given a vector $\mathfrak{c}\in\mathbb{N}^n$, the ideal $I_{\mathfrak{c}}$ is the ideal generated by those monomials…

Commutative Algebra · Mathematics 2025-06-03 Takayuki Hibi , Seyed Amin Seyed Fakhari

We provide a new combinatorial approach to study the minimal free resolutions of edge ideals, that is, quadratic square-free monomial ideals. With this method we can recover most of the known results on resolutions of edge ideals with…

Commutative Algebra · Mathematics 2007-05-23 Huy Tai Ha , Adam Van Tuyl

In this paper, we prove that for Noetherian graded families $\mathcal{I} = \{I_k\}_{k \ge 0}$ of homogeneous ideals, $\lim\limits_{k \to \infty} \frac{\mathrm{v}(I_k)}{k}$ exists, %equals $\lim\limits_{k \to \infty} \frac{\alpha(I_k)}{k}$,…

Commutative Algebra · Mathematics 2026-04-03 Mousumi Mandal , Partha Phukan

The \emph{linear refinement number} $\mathfrak{lr}$ is the minimal cardinality of a centered family in $[\omega]^\omega$ such that no linearly ordered set in $([\omega]^\omega,\subseteq^*)$ refines this family. The \emph{linear excluded…

General Topology · Mathematics 2016-05-03 Michał Machura , Saharon Shelah , Boaz Tsaban

It is proved that given any prime ideal $\mathfrak{p}$ of height at least 2 in a countable commutative noetherian ring $A$, there are uncountably many more dualizable objects in the $\mathfrak{p}$-local $\mathfrak{p}$-torsion stratum of the…

Commutative Algebra · Mathematics 2024-01-05 Jon F. Carlson , Srikanth B. Iyengar

The aim of this work is to study sets of values of fractional ideals of rings of algebroid curves and explore more deeply the symmetry that exists among sets of values of dual pairs of ideals when the ring is Gorenstein. We also express the…

Algebraic Geometry · Mathematics 2018-04-27 Abramo Hefez , Edison Marcavillaca Niño de Guzmán

We prove that if there is a real-valued measurable cardinal then the splitting number is $\aleph_1$. Likewise, if the continuum is real-valued measurable then the reaping number equals the continuum.

Logic · Mathematics 2018-06-06 Shimon Garti , Saharon Shelah

The aim of this paper is to extend Cohen structure theorem beyond local rings. Both Cohen structure theorem and Nagata's generalization of it are special cases of our results. We investigate for which rings $R$ there exists a maximal ideal…

Commutative Algebra · Mathematics 2025-02-14 Elena Caviglia , Amartya Goswami , Luca Mesiti

Let A and B be arbitrary sets with at least two elements. The arity gap of a function f: A^n \to B is the minimum decrease in its essential arity when essential arguments of f are identified. In this paper we study the arity gap of…

Rings and Algebras · Mathematics 2016-11-22 Miguel Couceiro , Erkko Lehtonen

Reduced ideals have been defined in the context of integer rings in quadratic number fields, and they are closely tied to the continued fraction algorithm. The notion of this type of ideal extends naturally to number fields of higher…

Number Theory · Mathematics 2019-06-04 George Jacobs

We show relative to strong hypotheses that patterns of compact cardinals in the universe, where a compact cardinal is one which is either strongly compact or supercompact, can be virtually arbitrary. Specifically, we prove if V is a model…

Logic · Mathematics 2007-05-23 Arthur W. Apter

For any cardinal number $\kappa$ and an index set $\Gamma$, $\Sigma_\kappa$-product of real lines consists of elements of ${\mathbb R}^\Gamma$ having $<\kappa$ nonzero coordinates. A compact space $K$ is $\kappa$-Corson compact if it can be…

General Topology · Mathematics 2023-07-10 Witold Marciszewski , Grzegorz Plebanek , Krzysztof Zakrzewski

Let $(R,\mathfrak{m},\Bbbk)$ be a regular local ring of dimension 3. Let $I$ be a Gorenstein ideal of $R$ of grade 3. It follows from a result of Buchsbaum and Eisenbud that there is a skew-symmetric matrix of odd size such that $I$ is…

Commutative Algebra · Mathematics 2024-04-05 Luigi Ferraro , W. Frank Moore

We show that for any uncountable cardinal $\lambda$, the category of sets of cardinality at least $\lambda$ and monomorphisms between them cannot appear as the category of point of a topos, in particular is not the category of models of a…

Category Theory · Mathematics 2020-05-11 Simon Henry

Let X be a projective variety, $\sigma$ an automorphism of X, L a $\sigma$-ample invertible sheaf on X, and Z a closed subscheme of X. Inside the twisted homogeneous coordinate ring $B = B(X, L, \sigma)$, let I be the right ideal of…

Rings and Algebras · Mathematics 2010-09-07 Susan J. Sierra

We study several cardinal, and ordinal--valued functions that are relatives of Hanf numbers. Let kappa be an infinite cardinal, and let T subseteq L_{kappa^+, omega} be a theory of cardinality <= kappa, and let gamma be an ordinal >=…

Logic · Mathematics 2016-09-07 Rami Grossberg , Saharon Shelah

In this article we produce Groebner bases for the defining ideal of a monomial curve that corresponds to an almost arithmetic sequence of positive integers, correcting previous work of Sengupta,(2003).

Commutative Algebra · Mathematics 2007-05-23 Ibrahim Al-Ayyoub

Let K/Q be Galois, and let eta in K* whose conjugates are multiplicatively independent. For a prime p, unramified, prime to eta, let np be the residue degree of p and gp the number of P I p, then let o\_P(eta) and o\_p(eta) be the orders of…

Number Theory · Mathematics 2021-08-06 Georges Gras

The ring of periodic distributions on ${\mathbb{R}}^{\tt d}$ with usual addition and with convolution is considered. Via Fourier series expansions, this ring is isomorphic to the ring ${\mathcal{S}}'({\mathbb{Z}}^{\tt d})$ of all maps…

Functional Analysis · Mathematics 2023-04-17 Amol Sasane

Let $\mathfrak{i}$ denote the minimal cardinality of a maximal independent family and let $\mathfrak{a}_T$ denote the minimal cardinality of a maximal family of pairwise almost disjoint subtrees of $2^{<\omega}$. Using a countable support…

Logic · Mathematics 2019-12-24 Vera Fischer