n | a(n) |
---|---|
1 | 2 |
2 | 4 |
3 | 9 |
4 | 21 |
5 | 46 |
6 | 99 |
7 | 215 |
8 | 464 |
9 | 999 |
10 | 2154 |
11 | 4641 |
12 | 9999 |
13 | 21544 |
14 | 46415 |
15 | 99999 |
16 | 215443 |
17 | 464158 |
18 | 999999 |
19 | 2154434 |
20 | 4641588 |
21 | 9999999 |
22 | 21544346 |
23 | 46415888 |
24 | 99999999 |
25 | 215443469 |
26 | 464158883 |
27 | 999999999 |
28 | 2154434690 |
29 | 4641588833 |
30 | 9999999999 |
[2,4,9,21,46,99,215,464,999,2154,4641,9999,21544, 46415,99999,215443,464158,999999,2154434,4641588, 9999999,21544346,46415888,99999999,215443469, 464158883,999999999,2154434690,4641588833, 9999999999] |