| Compact formula | 32[10] - 4[239] - 16[515] |
| Lehmer's measure | 1.78920 |
| References | Simson, Robert. Paper on series, enclosed in a letter to James Jurin, 1723. [Printed in "Account of the life and writings of Robert Simson, M.D., late professor of mathematics in the University of Glasgow" (pages 105–111) by Trail, William, 1812.] |