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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 9 |
| 10 | 9 |
| 11 | 29 |
| 12 | 29 |
| 13 | 137 |
| 14 | 137 |
| 15 | 1079 |
| 16 | 1079 |
| 17 | 13093 |
| 18 | 13093 |
| 19 | 250867 |
| 20 | 250867 |
| 21 | 6233403 |
| 22 | 6233403 |
| 23 | 218750525 |
| 24 | 218750525 |
| 25 | 11495073517 |
| 26 | 11495073517 |
| 27 | 872282781415 |
[1,1,1,1,1,1,1,1,9,9,29,29,137,137,1079,1079, 13093,13093,250867,250867,6233403,6233403, 218750525,218750525,11495073517,11495073517, 872282781415] |