M000000474: Euler's Machin-like formula

$$\pi=4\arctan\left(\frac{1}{2}\right)+4\arctan\left(\frac{1}{3}\right)$$
NameEuler's Machin-like formula
Compact formula4[2] + 4[3]
Lehmer's measure5.41783
References
Machin, John. Unpublished paper submitted to the Royal Society, 1706.