Machin-like formulae
M000000529
$$\pi=12\arctan\left(\frac{1}{3}\right)+4\arctan\left(\frac{1}{20}\right)-12\arctan\left(\frac{1}{23}\right)-12\arctan\left(\frac{1}{30}\right)+4\arctan\left(\frac{1}{1985}\right)$$
Compact formula
12[3] + 4[20] - 12[23] - 12[30] + 4[1985]
Lehmer's measure
4.57911