M000000051

$$\pi=13260\arctan\left(\frac{1}{7535}\right)+12888\arctan\left(\frac{1}{9703}\right)+4424\arctan\left(\frac{1}{57532}\right)-5284\arctan\left(\frac{1}{167318}\right)+1592\arctan\left(\frac{2}{529661}\right)-460\arctan\left(\frac{1}{664373}\right)+3436\arctan\left(\frac{1}{1048768}\right)-2500\arctan\left(\frac{1}{7042807}\right)$$