ترغب بنشر مسار تعليمي؟ اضغط هنا

On the Stanley Depth of Squarefree Veronese Ideals

172   0   0.0 ( 0 )
 نشر من قبل Yi-Huang Shen
 تاريخ النشر 2009
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

Let $K$ be a field and $S=K[x_1,...,x_n]$. In 1982, Stanley defined what is now called the Stanley depth of an $S$-module $M$, denoted $sdepth(M)$, and conjectured that $depth(M) le sdepth(M)$ for all finitely generated $S$-modules $M$. This conjecture remains open for most cases. However, Herzog, Vladoiu and Zheng recently proposed a method of attack in the case when $M = I / J$ with $J subset I$ being monomial $S$-ideals. Specifically, their method associates $M$ with a partially ordered set. In this paper we take advantage of this association by using combinatorial tools to analyze squarefree Veronese ideals in $S$. In particular, if $I_{n,d}$ is the squarefree Veronese ideal generated by all squarefree monomials of degree $d$, we show that if $1le dle n < 5d+4$, then $sdepth(I_{n,d})= floor{binom{n}{d+1}Big/binom{n}{d}}+d$, and if $dgeq 1$ and $nge 5d+4$, then $d+3le sdepth(I_{n,d}) le floor{binom{n}{d+1}Big/binom{n}{d}}+d$.



قيم البحث

اقرأ أيضاً

We give upper bounds for the Stanley depth of edge ideals of certain k-partite clutters. In particular, we generalize a result of Ishaq about the Stanley depth of the edge ideal of a complete bipartite graph. A result of Pournaki, Seyed Fakhari and Y assemi implies that the Stanleys conjecture holds for d-uniform complete d-partite clutters. Here we give a shorter and different proof of this fact.
Squarefree powers of edge ideals are intimately related to matchings of the underlying graph. In this paper we give bounds for the regularity of squarefree powers of edge ideals, and we consider the question of when such powers are linearly related o r have linear resolution. We also consider the so-called squarefree Ratliff property.
115 - Luca Amata , Marilena Crupi 2021
Let $K$ be a field and $S = K[x_1,dots,x_n]$ be a polynomial ring over $K$. We discuss the behaviour of the extremal Betti numbers of the class of squarefree strongly stable ideals. More precisely, we give a numerical characterization of the possible extremal Betti numbers (values as well as positions) of such a class of squarefree monomial ideals.
Let $S=K[x_1,ldots,x_n]$ be the polynomial ring in $n$ variables over a field $K$ and $Isubset S$ a squarefree monomial ideal. In the present paper we are interested in the monomials $u in S$ belonging to the socle $Soc(S/I^{k})$ of $S/I^{k}$, i.e., $u otin I^{k}$ and $ux_{i} in I^{k}$ for $1 leq i leq n$. We prove that if a monomial $x_1^{a_1}cdots x_n^{a_n}$ belongs to $Soc(S/I^{k})$, then $a_ileq k-1$ for all $1 leq i leq n$. We then discuss squarefree monomial ideals $I subset S$ for which $x_{[n]}^{k-1} in Soc(S/I^{k})$, where $x_{[n]} = x_{1}x_{2}cdots x_{n}$. Furthermore, we give a combinatorial characterization of finite graphs $G$ on $[n] = {1, ldots, n}$ for which $depth S/(I_{G})^{2}=0$, where $I_{G}$ is the edge ideal of $G$.
207 - Oana Olteanu 2011
We compute the minimal primary decomposition for completely squarefree lexsegment ideals. We show that critical squarefree monomial ideals are sequentially Cohen-Macaulay. As an application, we give a complete characterization of the completely squar efree lexsegment ideals which are sequentially Cohen-Macaulay and we also derive formulas for some homological invariants of this class of ideals.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا