12 citations · 28 across the 16 of their papers we have counts for
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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…
Generalized F-signatures of Hibi rings
Akihiro Higashitani, Yusuke Nakajima
The -signature is a numerical invariant defined by the number of free direct summands in the Frobenius push-forward, and it measures singularities in positive characteristic. It…
Remarks on divisorial ideals arising from dimer models
Yusuke Nakajima
The Jacobian algebra arising from a consistent dimer model is derived equivalent to crepant resolutions of a -dimensional Gorenstein toric singularity , and it i…
Ulrich modules over cyclic quotient surface singularities
Yusuke Nakajima, Ken-ichi Yoshida
In this paper, we characterize Ulrich modules over cyclic quotient surface singularities by using the notion of special Cohen-Macaulay modules. We also investigate the number of in…
Dual F-signature of Cohen-Macaulay modules over rational double points
Yusuke Nakajima
The dual -signature is a numerical invariant defined via the Frobenius morphism in positive characteristic. It is known that the dual -signature characterizes some singularit…
Dual F-signature of special Cohen-Macaulay modules over cyclic quotient surface singularities
Yusuke Nakajima
The notion of -signature is defined by C. Huneke and G. Leuschke and this numerical invariant characterizes some singularities. This notion is extended to finitely generated mod…
Generalized F-signature of invariant subrings
Mitsuyasu Hashimoto, Yusuke Nakajima
It is known that a certain invariant subring has finite -representation type. Thus, we can write the -module as a finite direct sum of finitely many -modules.…