4 papers
Almost Gorenstein edge rings of bipartite graphs and their -vectors
Yuta Hatasa, Koji Matsushita
We characterize bipartite graphs whose edge rings are almost Gorenstein. Using this characterization, we recover known results for two families of graphs. In addition, we show that…
Algebras with straightening laws on join- or meet-semidistributive lattices
Koji Matsushita, Sora Miyashita, Koichiro Tani
We study algebras with straightening laws on join- or meet-semidistributive lattices. We show that for a join-semidistributive (resp. meet-semidistributive) lattice, meet-distribut…
Pseudo-Gorenstein edge rings and a new family of almost Gorenstein edge rings
Yuta Hatasa, Nobukazu Kowaki, Koji Matsushita
In this paper, we study edge rings and their -polynomials. We investigate when edge rings are pseudo-Gorenstein, which means that the leading coefficients of the -polynomials…
Conditions of multiplicity and applications for almost Gorenstein graded rings
Koji Matsushita, Sora Miyashita
In this paper, we prove that if Cohen-Macaulay local/graded rings , and satisfy certain conditions regarding multiplicity and Cohen-Macaulay type, then almost Gorens…