M000000021

$$\pi=1416\arctan\left(\frac{1}{580}\right)+1132\arctan\left(\frac{1}{1710}\right)+332\arctan\left(\frac{1}{5827}\right)-908\arctan\left(\frac{2}{97059}\right)-48\arctan\left(\frac{2}{2513489}\right)-332\arctan\left(\frac{1}{1561886607}\right)+908\arctan\left(\frac{1}{14130722757}\right)$$