M000000409

$$\pi=10\arctan\left(\frac{1}{3}\right)-4\arctan\left(\frac{1}{53}\right)-2\arctan\left(\frac{1}{4443}\right)$$
Compact formula10[3] - 4[53] - 2[4443]
Lehmer's measure2.95000
References
Wrench Jr., J. W. The derivation of arctangent equalities (PhD thesis, Yale University), 1938.