M000172

$$\pi=19803492\arctan\left(\frac{2}{16840821}\right)+19637688\arctan\left(\frac{1}{24208144}\right)-20692676\arctan\left(\frac{1}{54610269}\right)-11748452\arctan\left(\frac{1}{63199427}\right)+41908120\arctan\left(\frac{1}{100656977}\right)+27146184\arctan\left(\frac{1}{115453918}\right)-19709864\arctan\left(\frac{2}{322564791}\right)+4516132\arctan\left(\frac{1}{385231007}\right)-32670944\arctan\left(\frac{1}{1304967682}\right)+10438408\arctan\left(\frac{1}{1595986592}\right)+6517024\arctan\left(\frac{2}{4532659739}\right)+44510496\arctan\left(\frac{2}{4949475989}\right)+2115052\arctan\left(\frac{1}{18986886768}\right)-26987860\arctan\left(\frac{2}{520629831511}\right)-10438408\arctan\left(\frac{1}{2517728913757}\right)$$
Compact formula19803492[16840821/2] + 19637688[24208144] - 20692676[54610269] - 11748452[63199427] + 41908120[100656977] + 27146184[115453918] - 19709864[322564791/2] + 4516132[385231007] - 32670944[1304967682] + 10438408[1595986592] + 6517024[4532659739/2] + 44510496[4949475989/2] + 2115052[18986886768] - 26987860[520629831511/2] - 10438408[2517728913757]
Lehmer's measure1.72180
References
ASN (27May10)(ΒΆΒΆ1.87953) (full reference coming soon)