5 papers
Integer Parameter Shifts in One-Variable Restrictions of Lauricella's
Ryunosuke Nakano
We construct rational functions of the coefficient index for one-variable restrictions of Lauricella's function at arguments related by cube roots of unity, with arbitrary in…
A codimension formula for intrinsic perturbation of -hypergeometric series
Ryunosuke Nakano
We study the canonical formal solution space of a homogeneous -hypergeometric system in a generic direction. We present as a finite-dimensional cokernel the quotient of that spa…
The Constant in Thomae-Type Formulas for Eight Points on the Complex Projective Line
Ryunosuke Nakano
We consider the family of cyclic fourfold covers of the complex projective line branched at the eight points . The period map…
The obstruction to intrinsic perturbation for -hypergeometric series
Ryunosuke Nakano
We show that, at a fake exponent of an -hypergeometric system and for an ordered negative support family, intrinsic perturbation within can produce a stri…
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…