English

Depth of powers of edge ideals of cycles and trees

Commutative Algebra 2023-08-03 v1

Abstract

Let II be the edge ideal of a cycle of length n5n \ge 5 over a polynomial ring S=k[x1,,xn]S = \mathrm{k}[x_1,\ldots,x_n]. We prove that for 2t<(n+1)/22 \le t < \lceil (n+1)/2 \rceil, depth(S/It)=nt+13.\operatorname{depth} (S/I^t) = \lceil \frac{n -t + 1}{3} \rceil. When G=TaG = T_{\mathbf{a}} is a starlike tree which is the join of kk paths of length a1,,aka_1, \ldots, a_k at a common root 11, we give a formula for the depth of powers of I(Ta)I(T_{\mathbf{a}}).

Keywords

Cite

@article{arxiv.2308.00874,
  title  = {Depth of powers of edge ideals of cycles and trees},
  author = {Nguyen Cong Minh and Tran Nam Trung and Thanh Vu},
  journal= {arXiv preprint arXiv:2308.00874},
  year   = {2023}
}