Good ideals and -ideals in two-dimensional normal singularities

T Okuma, K Watanabe, K Yoshida - Manuscripta Mathematica, 2016 - Springer
In this paper, we introduce the notion of p_ g pg-ideals and p_ g pg-cycles, which inherits
nice properties of integrally closed ideals on rational singularities. As an application, we …

Ulrich ideals and modules over two-dimensional rational singularities

S Goto, K Ozeki, R Takahashi, KI Watanabe… - Nagoya Mathematical …, 2016 - cambridge.org
The main aim of this paper is to classify Ulrich ideals and Ulrich modules over two-
dimensional Gorenstein rational singularities (rational double points) from a geometric point …

Normal Hilbert coefficients and elliptic ideals in normal two-dimensional singularities

T Okuma, ME Rossi, K Watanabe… - Nagoya Mathematical …, 2022 - cambridge.org
Let be an excellent two-dimensional normal local domain. In this paper, we study the elliptic
and the strongly elliptic ideals of A with the aim to characterize elliptic and strongly elliptic …

[HTML][HTML] A characterization of two-dimensional rational singularities via core of ideals

T Okuma, K Watanabe, K Yoshida - Journal of Algebra, 2018 - Elsevier
The notion of p g-ideals for normal surface singularities has been proved to be very useful.
On the other hand, the core of ideals has been proved to be very important concept and also …

On the canonical ideals of one-dimensional Cohen–Macaulay local rings

J Elias - Proceedings of the Edinburgh Mathematical Society, 2016 - cambridge.org
In this paper we consider the problem of explicitly finding canonical ideals of one-
dimensional Cohen–Macaulay local rings. We show that Gorenstein ideals contained in a …

On maximally elliptic singularities

SST Yau - Transactions of the American Mathematical Society, 1980 - ams.org
Let p be the unique singularity of a normal two-dimensional Stein space V. Let m be the
maximal ideal in $ _V {\mathcal {O} _p} $, the local ring of germs of holomorphic functions at …

Hilbert–Kunz multiplicity, McKay correspondence and good ideals¶ in two-dimensional rational singularities

K Watanabe, K Yoshida - manuscripta mathematica, 2001 - Springer
Hilbert–Kunz multiplicity is known to be a very mysterious invariant of a ring or an ideal. We
will show a very beautiful formula on Hilbert–Kunz multiplicity for integrally closed ideals in …

Cohomology of ideals in elliptic surface singularities

T Okuma - Illinois Journal of Mathematics, 2017 - projecteuclid.org
We introduce the the normal reduction number of two-dimensional normal singularities and
prove that elliptic singularity has normal reduction number two. We also prove that for a two …

A Gorenstein Criterion for Strongly F-Regular and Log Terminal Singularities

AK Singh, S Takagi, M Varbaro - … Mathematics Research Notices, 2017 - academic.oup.com
A conjecture of Hirose, Watanabe, and Yoshida offers a characterization of when a standard
graded strongly-regular ring is Gorenstein, in terms of an-pure threshold. We prove this …

[PDF][PDF] Classification of two-dimensional F-regular and F-pure singularities

N Hara - Advances in Mathematics, 1998 - core.ac.uk
The notions of F-regularity and F-purity for rings of characteristic p> 0, which are introduced
by Hochster and Huneke [HH1] and Hochster and Roberts [HR], respectively, are now …