English

Cohen-Macaulay local rings with $e_2 = e_1-e+1$

Commutative Algebra 2020-11-13 v1

Abstract

In this paper we study Cohen-Macaulay local rings of dimension dd, multiplicity ee and second Hilbert coefficient e2e_2 in the case e2=e1e+1e_2 = e_1 - e + 1. Let h=μ(m)dh = \mu(\mathfrak{m}) - d. If e20e_2 \neq 0 then in our case we can prove that type Aeh1A \geq e - h -1. If type A=eh1A = e - h -1 then we show that the associated graded ring G(A)G(A) is Cohen-Macaulay. In the next case when type A=ehA = e - h we determine all possible Hilbert series of AA. In this case we show that the Hilbert Series of AA completely determines depth G(A)G(A).

Keywords

Cite

@article{arxiv.2011.06197,
  title  = {Cohen-Macaulay local rings with $e_2 = e_1-e+1$},
  author = {Ankit Mishra and Tony J. Puthenpurakal},
  journal= {arXiv preprint arXiv:2011.06197},
  year   = {2020}
}

Comments

arXiv admin note: text overlap with arXiv:1907.11502

R2 v1 2026-06-23T20:07:09.246Z