4 citations · 5 across the 3 of their papers we have counts for
6 papers
A commutative noetherian local ring of embedding dimension 4 having a transcendental series of Betti numbers
Jan-Erik Roos
We construct a ring with the properties of the title of the paper. We also construct some other local rings of embedding dimension 4 with exotic properties. Among the methods used…
Homological Properties of the Homology Algebra of the Koszul Complex of a Local Ring. Examples and Questions
Jan-Erik Roos
Let be a local commutative noetherian ring and the homology ring of the corresponding Koszul complex. We study the homological properties of in particular the so-ca…
A Gorenstein numerical semi-group ring having a transcendental series of Betti numbers
Clas Löfwall, Samuel Lundqvist, Jan-Erik Roos
We prove in particular that the Gorenstein numerical semigroup ring generated by (36,48,50,52,56,60,66,67,107,121,129,135) has a transcendental series of Betti numbers. The methods…
Three-Dimensional Manifolds, Skew-Gorenstein Rings and their Cohomology
Jan-Erik Roos
Graded skew-commutative rings occur often in practice. Here are two examples: 1) The cohomology ring of a compact three-dimensional manifold. 2) The cohomology ring of the compleme…
Three-Dimensional Manifolds, Skew-Gorenstein Rings and their Cohomology
Jan-Erik Roos
Graded skew-commutative rings occur often in practice. Here are two examples: 1) The cohomology ring of a compact three-dimensional manifold. 2) The cohomology ring of the compleme…
The homotopy Lie algebra of a complex hyperplane arrangement is not necessarily finitely presented
Jan-Erik Roos
We present a theory that produces several examples where the homotopy Lie algebra of a complex hyperplane arrangement is not finitely presented. We also present examples of hyperpl…