25 citations · 144 across the 32 of their papers we have counts for
30 papers · 1 filter
Nearly Gorenstein blow-up algebras over two-dimensional regular local rings
Naoki Endo, Ken-ichi Yoshida
In this paper, we slightly extend the framework of nearly Gorenstein graded rings introduced by Herzog-Hibi-Stamate, and investigate the nearly Gorenstein property of the blow-up a…
Gorensteinness for normal tangent cones of elliptic ideals
Tomohiro Okuma, Kei-ichi Watanabe, Ken-ichi Yoshida
Let be a two-dimensional excellent normal Gorenstein local domain. In this paper, we characterize elliptic ideals for its normal tangent cone to…
Normal Hilbert coefficients and elliptic ideals in normal two-dimensional singularities
Tomohiro Okuma, Maria Evelina Rossi, Kei-ichi Watanabe +1
Let be an excellent two-dimensional normal local domain. In this paper we study the elliptic and the strongly elliptic ideals of with the aim to characterize…
Lower bounds on Hilbert--Kunz multiplicities and maximal F-signatures
Jack Jeffries, Yusuke Nakajima, Ilya Smirnov +2
Hilbert-Kunz multiplicity and F-signature are numerical invariants of commutative rings in positive characteristic that measure severity of singularities: for a regular ring both i…
The normal reduction number of two-dimensional cone-like singularities
Tomohiro Okuma, Kei-ichi Watanabe, Ken-ichi Yoshida
Let be a normal two-dimensional local ring and an -primary integrally closed ideal with a minimal reduction . Then we calculate the numbers:…
Normal reduction numbers for normal surface singularities with application to elliptic singularities of Brieskorn type
Tomohiro Okuma, Kei-ichi Watanabe, Ken-ichi Yoshida
In this paper, we give a formula for normal reduction number of an integrally closed -primary ideal of a -dimensional normal local ring in terms o…