Ryunosuke Nakano

collaborators

3 papers

math.AG2026

The Constant in Thomae-Type Formulas for Eight Points on the Complex Projective Line

Ryunosuke Nakano

We consider the family of cyclic fourfold covers $w^{4} = \prod_{j = 1}^{7} (z - x_{j})$ of the complex projective line branched at the eight points $x_{1}, \dots, x_{7}, \infty$ . The period map…

math.AG2026

Obstructions to intrinsic perturbation for $A$ -hypergeometric series

Ryunosuke Nakano

We show that, at a fake exponent of an $A$ -hypergeometric system and for an ordered negative support family, intrinsic perturbation within $ker_{Z} (A)$ can produce a stri…

math.AG2025

The algebro-geometric aspect of the iterated limit of a quaternary of means of four terms

Keiji Matsumoto, Ryunosuke Nakano

We study the iterated limit of a quaternary of means of four terms through the period map from the family of cyclic fourfold coverings of the complex projective line branching at s…

The Constant in Thomae-Type Formulas for Eight Points on the Complex Projective Line

Obstructions to intrinsic perturbation for A-hypergeometric series

The algebro-geometric aspect of the iterated limit of a quaternary of means of four terms

Obstructions to intrinsic perturbation for $A$ -hypergeometric series