Kawasaki's Riemann–Roch formula
In differential geometry, Kawasaki's Riemann–Roch formula, introduced by Tetsuro Kawasaki, is the Riemann–Roch formula for orbifolds. It can compute the Euler characteristic of an orbifold.
Source: Wikipedia — Kawasaki's Riemann–Roch formula (CC BY-SA 4.0)