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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 | 33 |
| 12 | 33 |
| 13 | 105 |
| 14 | 105 |
| 15 | 825 |
| 16 | 825 |
| 17 | 13503 |
| 18 | 13503 |
| 19 | 390699 |
| 20 | 390699 |
| 21 | 9339771 |
| 22 | 9339771 |
[1,1,1,1,1,1,1,1,9,9,33,33,105,105,825,825,13503, 13503,390699,390699,9339771,9339771] |