M000000386

$$\pi=48\arctan\left(\frac{1}{17}\right)+12\arctan\left(\frac{1}{57}\right)+20\arctan\left(\frac{1}{99}\right)-28\arctan\left(\frac{1}{307}\right)$$

Compact formula	`48[17] + 12[57] + 20[99] - 28[307]`
Lehmer's measure	2.28539
References	Størmer, Carl. Solution complète en nombres entiers m, n, x, y et k de l'équation marctang(1/x) + narctang(1/y) = kπ/4, chapter 11 in Skrifter udgivne af Vidensakbsselskabet i Christiania I. Mathematisk-naturvidenskabelig klasse, 11.1–11.21, 1896. Download references as BibTeΧ