M000000341

$$\pi=28\arctan\left(\frac{1}{8}\right)-16\arctan\left(\frac{1}{47}\right)+8\arctan\left(\frac{1}{247057}\right)-4\arctan\left(\frac{1}{740943}\right)$$

Compact formula	`28[8] - 16[47] + 8[247057] - 4[740943]`
Lehmer's measure	2.06115
References	Wetherfield, Michael Roby and Chien-Lih, Hwang. Computing pi: Lists of Machin-type (inverse cotangent) identities for pi/4, [Online; accessed 04-February-2024], 2013. [web.archive.org/web/20240204042153/http] [Found by Koepp in 1994.] Download references as BibTeΧ