M000000118

$$\pi=68\arctan\left(\frac{1}{23}\right)+32\arctan\left(\frac{1}{182}\right)+20\arctan\left(\frac{2}{3611}\right)+20\arctan\left(\frac{1}{623098}\right)$$

Compact formula	`68[23] + 32[182] + 20[3611/2] + 20[623098]`
Lehmer's measure	1.65646
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 Amrik Singh Nimbran on 16 September 2009.] Download references as BibTeΧ