English

Super-stretched and graded countable Cohen-Macaulay type

Commutative Algebra 2013-07-24 v2

Abstract

We define what it means for a Cohen-Macaulay ring to to be super-stretched and show that Cohen-Macaulay rings of graded countable Cohen-Macaulay type are super-stretched. We use this result to show that rings of graded countable Cohen-Macaulay type, and positive dimension, have possible h-vectors (1), (1,n), or (1,n,1). Further, one dimensional standard graded Gorenstein rings of graded countable type are shown to be hypersurfaces; this result is not known in higher dimensions. In the non-Gorenstein case, rings of graded countable Cohen-Macaulay type of dimension larger than 2 are shown to be of minimal multiplicity.

Keywords

Cite

@article{arxiv.1301.3593,
  title  = {Super-stretched and graded countable Cohen-Macaulay type},
  author = {Branden Stone},
  journal= {arXiv preprint arXiv:1301.3593},
  year   = {2013}
}

Comments

20 pages

R2 v1 2026-06-21T23:10:10.939Z