M000000635

$$\pi=-122\arctan\left(\frac{1}{2}\right)+244\arctan\left(\frac{1}{4}\right)-34\arctan\left(\frac{1}{463}\right)+12\arctan\left(\frac{1}{2682}\right)+6\arctan\left(\frac{1}{8827}\right)+34\arctan\left(\frac{1}{390112}\right)$$