activity
20092026
most citedThe Euler system of cyclotomic units and higher Fitting ideals

1 citations · 1 across the 13 of their papers we have counts for

collaborators

14 papers

cs.AI2026

Algebraic Quantum Intelligence: A New Framework for Reproducible Machine Creativity

Kazuo Yano, Jonghyeok Lee, Tae Ishitomi +26

Large language models (LLMs) have achieved remarkable success in generating fluent and contextually appropriate text; however, their capacity to produce genuinely creative outputs…

math.NT2023

Periods modulo of integer sequences associated with division polynomials of genus curves

Yasuhiro Ishitsuka, Tetsushi Ito, Tatsuya Ohshita +2

We study an integer sequence associated with Cantor's division polynomials of a genus 2 curve having an integral point. We show that the reduction modulo of such a sequence is…

math.NT2022

The Hodge Realization of the Polylogarithm and the Shintani Generating Class for Totally Real Fields

Kenichi Bannai, Hohto Bekki, Kei Hagihara +3

In this article, we construct the Hodge realization of the polylogarithm class in the equivariant Deligne-Beilinson cohomology of a certain algebraic torus associated to a totally…

math.NT2022

Asymptotic behavior of class groups and cyclotomic Iwasawa theory of elliptic curves

Toshiro Hiranouchi, Tatsuya Ohshita

In this article, we study a relation between certain quotients of ideal class groups and the cyclotomic Iwasawa module of the Pontrjagin dual of the fine Selmer group of…

math.NT2021

The arithmetic of a twist of the Fermat quartic

Yasuhiro Ishitsuka, Tetsushi Ito, Tatsuya Ohshita

We study the arithmetic of the twist of the Fermat quartic defined by which has no -rational point. We calculate the Mordell--Weil group of the Ja…

math.NT2020

The local-global property for bitangents of plane quartics

Yasuhiro Ishitsuka, Tetsushi Ito, Tatsuya Ohshita +2

We study the arithmetic of bitangents of smooth quartics over global fields. With the aid of computer algebra systems and using Elsenhans--Jahnel's results on the inverse Galois pr…

math.NT2018

Asymptotic lower bound of class numbers along a Galois representation

Tatsuya Ohshita

Let T be a free Z_p-module of finite rank equipped with a continuous Z_p-linear action of the absolute Galois group of a number field K satisfying certain conditions. In this artic…

math.NT2018

On infinite extensions of Dedekind domains, upper semicontinuous functions and the ideal class semigroups

Tatsuya Ohshita

In this article, we study the monoid of fractional ideals and the ideal class semigroup of an arbitrary given one dimensional normal domain O obtained by an infinite integral exten…

math.NT2018

On algorithms to obtain linear determinantal representations of smooth plane curves of higher degree

Yasuhiro Ishitsuka, Tetsushi Ito, Tatsuya Ohshita

We give two algorithms to compute linear determinantal representations of smooth plane curves of any degree over any field. As particular examples, we explicitly give representativ…

math.NT2018

Explicit calculation of the mod 4 Galois representation associated with the Fermat quartic

Yasuhiro Ishitsuka, Tetsushi Ito, Tatsuya Ohshita

We use explicit methods to study the 4-torsion points on the Jacobian variety of the Fermat quartic. With the aid of computer algebra systems, we explicitly give a basis of the gro…

math.NT2017

Euler systems for Galois deformations and the pseudo-isomorphism class of the dual of fine Selmer groups

Tatsuya Ohshita

In this article, we study the pseudo-isomorphism class of the dual fine Selmer group attached to a -adic Galois deformation whose deformation ring is isomorphic to the r…

math.NT2017

On higher Fitting ideals of Iwasawa modules of ideal class groups over imaginary quadratic fields and Euler systems of elliptic units II

Tatsuya Ohshita

In our previous work, by using Kolyvagin derivatives of elliptic units, we constructed ideals C_i of the Iwasawa algebra, and proved that the ideals C_i become "upper bounds" of th…

math.NT2011

On the higher Fitting ideals of Iwasawa modules of ideal class groups over real abelian fields

Tatsuya Ohshita

Kurihara established a refinement of the minus-part of the Iwasawa main conjecture for totally real number fields using the higher Fitting ideals. In this paper, by using Kurihara'…

math.NT2009★ 1 cited

The Euler system of cyclotomic units and higher Fitting ideals

Tatsuya Ohshita

Kurihara established a refinement of the minus-part of the Iwasawa main conjecture for totally real number fields using the higher Fitting ideals. In this paper, we study the highe…