Very accurate pi approximation
SMRTR summary
A highly accurate approximation for π uses the formula 3 log(640320) / √163, correct to 15 decimal places. This approximation is closely related to Ramanujan's constant, which is famously almost an integer, and can be derived from the same mathematical relationship.
SMRTR provides this summary for quick context. The original article belongs to John D. Cook.
Read the original article