A naive-topological study of the contiguity relations for hypergeometric functions
Banach Center Publications 69 (2005), 257-268 MSC: Primary 33C05. DOI: 10.4064/bc69-0-20
When the parameters are real, the hypergeometric equation defines a Schwarz triangle. We study a combinatorial-topological property of the Schwarz triangle when the three angles are not necessarily less than $\pi$.