M000003556

$$\pi=16\arctan\left(\frac{1}{5}\right)-4\arctan\left(\frac{1}{9}\right)+8\arctan\left(\frac{1}{12}\right)+16\arctan\left(\frac{1}{21}\right)-4\arctan\left(\frac{1}{32}\right)-16\arctan\left(\frac{1}{34}\right)-16\arctan\left(\frac{1}{55}\right)-8\arctan\left(\frac{1}{70}\right)$$

Compact formula	`16[5] - 4[9] + 8[12] + 16[21] - 4[32] - 16[34] - 16[55] - 8[70]`
Lehmer's measure	6.59547