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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 1 |
| 10 | 1 |
| 11 | 3 |
| 12 | 3 |
| 13 | 13 |
| 14 | 13 |
| 15 | 31 |
| 16 | 31 |
| 17 | 77 |
| 18 | 77 |
| 19 | 447 |
| 20 | 447 |
| 21 | 3609 |
| 22 | 3609 |
| 23 | 25623 |
[1,1,1,1,1,1,1,1,1,1,3,3,13,13,31,31,77,77,447, 447,3609,3609,25623] |