M000171

$$\pi=29002772\arctan\left(\frac{1}{36226953}\right)+46329268\arctan\left(\frac{1}{78739287}\right)+55392476\arctan\left(\frac{1}{144235918}\right)+62020556\arctan\left(\frac{2}{322564791}\right)+141523560\arctan\left(\frac{1}{193788912}\right)+5375732\arctan\left(\frac{1}{201229582}\right)+66811928\arctan\left(\frac{1}{284862638}\right)-14261956\arctan\left(\frac{1}{1514342682}\right)-1637580\arctan\left(\frac{2}{4204410541}\right)-8154604\arctan\left(\frac{1}{7427844818}\right)+82332092\arctan\left(\frac{1}{7959681215}\right)-153624104\arctan\left(\frac{1}{18710140581}\right)+42477072\arctan\left(\frac{2}{75525552427}\right)+29427040\arctan\left(\frac{1}{57821838732}\right)+3752632\arctan\left(\frac{2}{1087840667761}\right)+38573116\arctan\left(\frac{1}{169838669284032}\right)$$
Compact formula29002772[36226953] + 46329268[78739287] + 55392476[144235918] + 62020556[322564791/2] + 141523560[193788912] + 5375732[201229582] + 66811928[284862638] - 14261956[1514342682] - 1637580[4204410541/2] - 8154604[7427844818] + 82332092[7959681215] - 153624104[18710140581] + 42477072[75525552427/2] + 29427040[57821838732] + 3752632[1087840667761/2] + 38573116[169838669284032]
Lehmer's measure1.72151
References
HCL (07Mar04) (full reference coming soon)