3 papers
math.CO2025
Stable hyperplane arrangements
Toshio Oshima
We classify complex hyperplane arrangements whose intersection posets satisfy for $i=1,\dot…
math.CA2025
Middle convolutions of KZ-type equations and single-elimination tournaments
Toshio Oshima
We introduce an extension of the generalized Riemann scheme for Fuchsian ordinary differential equations in the case of KZ-type equations. This extension describes the local struct…
math.RT2025
Algorithm classifying roots of star-shaped Kac-Moody root systems
Toshio Oshima
For a star-shaped Kac-Moody root system, we provide an effective algorithm to obtain representatives of the Weyl group orbits of roots with a given norm and implement it as a compu…