M000188

$$\pi=58429812\arctan\left(\frac{1}{27872057}\right)+12119834\arctan\left(\frac{1}{42443947}\right)+25965436\arctan\left(\frac{1}{144235918}\right)+8373138\arctan\left(\frac{2}{322564791}\right)+63805544\arctan\left(\frac{1}{201229582}\right)+76376716\arctan\left(\frac{1}{284862638}\right)-29002772\arctan\left(\frac{1}{468195145}\right)-14261956\arctan\left(\frac{1}{1514342682}\right)-16902228\arctan\left(\frac{2}{3472598789}\right)+27789460\arctan\left(\frac{2}{4204410541}\right)+20848168\arctan\left(\frac{1}{7427844818}\right)+57687446\arctan\left(\frac{1}{7959681215}\right)+42052804\arctan\left(\frac{2}{75525552427}\right)-45905000\arctan\left(\frac{1}{64506738863}\right)-13149596\arctan\left(\frac{2}{1087840667761}\right)-2973758\arctan\left(\frac{1}{169838669284032}\right)$$
Compact formula58429812[27872057] + 12119834[42443947] + 25965436[144235918] + 8373138[322564791/2] + 63805544[201229582] + 76376716[284862638] - 29002772[468195145] - 14261956[1514342682] - 16902228[3472598789/2] + 27789460[4204410541/2] + 20848168[7427844818] + 57687446[7959681215] + 42052804[75525552427/2] - 45905000[64506738863] - 13149596[1087840667761/2] - 2973758[169838669284032]
Lehmer's measure1.73313
References
MRW (12Aug06) (full reference coming soon)