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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 1 |
| 4 | 45 |
| 5 | 5 |
| 6 | 315 |
| 7 | 189 |
| 8 | 2025 |
| 9 | 4725 |
| 10 | 467775 |
| 11 | 1485 |
| 12 | 42567525 |
| 13 | 212837625 |
| 14 | 91216125 |
| 15 | 42567525 |
| 16 | 97692469875 |
| 17 | 516891375 |
| 18 | 9280784638125 |
| 19 | 236238154425 |
| 20 | 43752270436875 |
| 21 | 714620417135625 |
| 22 | 147926426347074375 |
| 23 | 53123043290625 |
| 24 | 48076088562799171875 |
[1,1,3,1,45,5,315,189,2025,4725,467775,1485, 42567525,212837625,91216125,42567525,97692469875, 516891375,9280784638125,236238154425, 43752270436875,714620417135625,147926426347074375, 53123043290625,48076088562799171875] |