Czechoslovak Mathematical Journal, Vol. 67, No. 3, pp. 753-766, 2017


Depth and Stanley depth of the facet ideals of some classes of simplicial complexes

Xiaoqi Wei, Yan Gu

Received April 7, 2016.   First published August 8, 2017.

Abstract:  Let $\Delta_{n,d}$ (resp. $\Delta_{n,d}'$) be the simplicial complex and the facet ideal $I_{n,d}=(x_1\cdots x_d,x_{d-k+1}\cdots x_{2d-k},\ldots,x_{n-d+1}\cdots x_n)$ (resp. $J_{n,d}=(x_1\cdots x_d,x_{d-k+1}\cdots x_{2d-k},\ldots,x_{n-2d+2k+1}\cdots x_{n-d+2k},x_{n-d+k+1}\cdots x_nx_1\cdots x_k)$). When $d\geq2k+1$, we give the exact formulas to compute the depth and Stanley depth of quotient rings $S/J_{n,d}$ and $S/I_{n,d}^t$ for all $t\geq1$. When $d=2k$, we compute the depth and Stanley depth of quotient rings $S/J_{n,d}$ and $S/I_{n,d}$, and give lower bounds for the depth and Stanley depth of quotient rings $S/I_{n,d}^t$ for all $t\geq1$.
Keywords:  monomial ideal; facet ideal; depth; Stanley depth
Classification MSC:  13C15, 13P10, 13F20, 13F55


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Affiliations:   Xiaoqi Wei, Yan Gu (corresponding author), School of Mathematical Sciences, Soochow University, No. 1 Shizi Street, Suzhou 215006, Jiangsu, P. R. China, e-mail: weixiaoqi1989@sina.com, guyan@suda.edu.cn


 
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