M000109

$$\pi=332\arctan\left(\frac{1}{185}\right)+664\arctan\left(\frac{1}{443}\right)-264\arctan\left(\frac{1}{1710}\right)+244\arctan\left(\frac{1}{105218}\right)+284\arctan\left(\frac{2}{2513489}\right)-88\arctan\left(\frac{1}{7167807}\right)$$
Compact formula332[185] + 664[443] - 264[1710] + 244[105218] + 284[2513489/2] - 88[7167807]
Lehmer's measure1.63720
References
HCL (23Sep04) (full reference coming soon)