(OEIS A001620) was calculated to 16 digits by Euler in 1781 and to 32 decimal places by Mascheroni (1790), although only the first 19 decimal places were correct. It was subsequently computed to 40 correct decimal placed by Soldner in 1809 and verified by Gauss and Nicolai in 1812 (Havil 2003, pp. 89-90). No quadratically converging algorithm for computing is known (Bailey 1988).
The following table summarizes some record computations.
decimal digit | date | reference |
Oct. 1999 | X. Gourdon and P. Demichel (Gourdon and Sebah) | |
Dec. 8, 2006 | Alexander J. Yee (Yee 2006; United Press International 2007) | |
? | S. Kondo | |
Mar. 13, 2009 | A. Yee |
The Earls sequence (starting position of copies of the digit ) for is given for , 2, ... by 5, 139, 163, 10359, 86615, 193446, 236542, 6186099, 36151186, ... (OEIS A224826).
-constant primes occur at 1, 3, 40, 185, 1038, 22610, 179849, ... (A065815) decimal digits.
The starting positions of the first occurrence of , 1, 2, ... in the decimal expansion of (excluding the initial 0 to the left of the decimal point) are 11, 5, 4, 14, 9, 1, 7, 2, 16, 10, ... (OEIS A229192).
Scanning the decimal expansion of until all -digit numbers have occurred, the last 1-, 2-, ... digit numbers appearing are 8, 18, 346, 2778, 84514, ... (OEIS A000000), which end at digits 16, 658, 6600, 91101, 1384372, ... (OEIS A000000).
It is not known if is normal, but the following table giving the counts of digits in the first terms shows that the decimal digits are very uniformly distributed up to at least .
OEIS | 10 | 100 | ||||||||
0 | A000000 | 0 | 11 | 111 | 1004 | 10065 | 100150 | 999853 | 10001768 | 99998397 |
1 | A000000 | 1 | 6 | 95 | 1006 | 9974 | 100143 | 1000601 | 9996653 | 100002318 |
2 | A000000 | 1 | 10 | 97 | 967 | 9821 | 99796 | 998927 | 9998112 | 99986624 |
3 | A000000 | 0 | 9 | 108 | 976 | 9973 | 100194 | 1000766 | 9999460 | 99984204 |
4 | A000000 | 1 | 10 | 90 | 1014 | 9870 | 99783 | 1001444 | 10007542 | 100011681 |
5 | A000000 | 2 | 9 | 99 | 980 | 10200 | 100110 | 1002104 | 10001985 | 99996372 |
6 | A000000 | 2 | 14 | 90 | 988 | 10103 | 100170 | 999530 | 9996871 | 100014127 |
7 | A000000 | 2 | 13 | 116 | 1014 | 9877 | 99682 | 998692 | 9997487 | 99988819 |
8 | A000000 | 0 | 7 | 81 | 1033 | 10114 | 100135 | 998534 | 9998182 | 100006202 |
9 | A000000 | 1 | 11 | 113 | 1018 | 10003 | 99837 | 999549 | 10001940 | 100011256 |