Bailey–Borwein–Plouffe formula
The Bailey–Borwein–Plouffe formula (BBP formula) is a formula for π. It was discovered in 1995 by Simon Plouffe and is named after the authors of the article in which it was published, David H. Bailey, Peter Borwein, and Plouffe.
Source: Wikipedia — Bailey–Borwein–Plouffe formula (CC BY-SA 4.0)