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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 | 1 |
| 12 | 1 |
| 13 | 7 |
| 14 | 7 |
| 15 | 21 |
| 16 | 21 |
| 17 | 55 |
| 18 | 55 |
| 19 | 263 |
| 20 | 263 |
| 21 | 1645 |
| 22 | 1645 |
| 23 | 13423 |
| 24 | 13423 |
[1,1,1,1,1,1,1,1,1,1,1,1,7,7,21,21,55,55,263,263, 1645,1645,13423,13423] |