M000000153

$$\pi=136\arctan\left(\frac{1}{53}\right)+60\arctan\left(\frac{1}{107}\right)+68\arctan\left(\frac{1}{4443}\right)-20\arctan\left(\frac{1}{110443}\right)+20\arctan\left(\frac{1}{4841182}\right)$$
Compact formula136[53] + 60[107] + 68[4443] - 20[110443] + 20[4841182]
Lehmer's measure1.69474
References
Chien-Lih, Hwang. More Machin-type identities, The Mathematical Gazette 81(490), 120–121, 1997. [DOI: 10.2307/3618793]

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 HCL on 24 June 1995.]