On the index of powers of edge ideals

被引:13
作者
Bigdeli, Mina [1 ]
Herzog, Juergen [2 ]
Zaare-Nahandi, Rashid [1 ]
机构
[1] Inst Adv Studies Basic Sci, Dept Math, Zanjan 451951159, Iran
[2] Univ Duisburg Essen, Fachbereich Math, Essen, Germany
关键词
Edge ideals; index; powers of ideals; resolutions; REGULARITY; SYZYGIES;
D O I
10.1080/00927872.2017.1339058
中图分类号
O1 [数学];
学科分类号
0701 ; 070101 ;
摘要
The index of a graded ideal measures the number of linear steps in the graded minimal free resolution of the ideal. In this paper, we study the index of powers and squarefree powers of edge ideals. Our results indicate that the index as a function of the power of an edge ideal / is strictly increasing if / is linearly presented. Examples show that this needs not to be the case for monomial ideals generated in degree greater than two.
引用
收藏
页码:1080 / 1095
页数:16
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