We study strong indispensability of minimal free resolutions of semigroup rings focusing on
the operation of gluing used in the literature to take examples with a special property and …

For some numerical semigroup rings of small embedding dimension, namely those of
embedding dimension 3, and symmetric or pseudosymmetric of embedding dimension 4 …

We construct a minimal free resolution of the semigroup ring k [C] in terms of minimal
resolutions of k [A] and k [B] when< C> is a numerical semigroup obtained by gluing two …

This survey presents recent results on minimal free resolutions of numerical semigroup
rings. We focus on two classes of numerical semigroups where the resolution is explicitly …

We collect some open problems about minimal presentations of numerical semigroups and,
more generally, about defining ideals and free resolutions of their semigroup rings and …

Abstract A semigroup⟨ C⟩ in N n is a gluing of⟨ A⟩ and⟨ B⟩ if its finite set of generators C
splits into two parts, C= k 1 A⊔ k 2 B with k 1, k 2≥ 1, and the defining ideals of the …

In this paper, we show that CLn, the chain with n elements, is efficient and that the direct
product CLm× CLn is inefficient. Moreover, we embed any finitely presented semigroup S …

We study almost symmetric numerical semigroups and semigroup rings. We describe a
characteristic property of the minimal free resolution of the semigroup ring of an almost …

FINITE PRESENTABILITY OF SEMIGROUP CONSTRUCTIONS Page 1 April 5, 2002 17:2
WSPC/132-IJAC 00089 International Journal of Algebra and Computation, Vol. 12, Nos. 1 & 2 …

This paper studies Young diagrams of symmetric and pseudo-symmetric numerical
semigroups and describes new operations on Young diagrams as well as numerical …