Machin-like formulae
M000000511
$$\pi=16\arctan\left(\frac{1}{4}\right)-16\arctan\left(\frac{1}{21}\right)-8\arctan\left(\frac{1}{577}\right)-4\arctan\left(\frac{1}{1393}\right)$$
Compact formula
16[4] - 16[21] - 8[577] - 4[1393]
Lehmer's measure
3.09750