Machin-like formulae
M000000527
$$\pi=8\arctan\left(\frac{1}{3}\right)-8\arctan\left(\frac{1}{4}\right)+20\arctan\left(\frac{1}{7}\right)-8\arctan\left(\frac{1}{30}\right)-8\arctan\left(\frac{1}{182}\right)$$
Compact formula
8[3] - 8[4] + 20[7] - 8[30] - 8[182]
Lehmer's measure
6.05961