Machin-like formulae
M000388
$$\pi=32\arctan\left(\frac{1}{8}\right)-16\arctan\left(\frac{1}{18}\right)+12\arctan\left(\frac{1}{239}\right)$$
Compact formula
32[8] - 16[18] + 12[239]
Lehmer's measure
2.32440
References
STØRMER (1896)
(full reference coming soon)