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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 3 |
| 5 | 15 |
| 6 | 45 |
| 7 | 315 |
| 8 | 315 |
| 9 | 2835 |
| 10 | 14175 |
| 11 | 155925 |
| 12 | 467775 |
| 13 | 6081075 |
| 14 | 42567525 |
| 15 | 58046625 |
| 16 | 638512875 |
| 17 | 10854718875 |
| 18 | 97692469875 |
| 19 | 1856156927625 |
| 20 | 9280784638125 |
| 21 | 194896477400625 |
| 22 | 2143861251406875 |
| 23 | 49308808782358125 |
| 24 | 147926426347074375 |
| 25 | 217538862275109375 |
| 26 | 4370553505709015625 |
[1,1,3,3,15,45,315,315,2835,14175,155925,467775, 6081075,42567525,58046625,638512875,10854718875, 97692469875,1856156927625,9280784638125, 194896477400625,2143861251406875, 49308808782358125,147926426347074375, 217538862275109375,4370553505709015625] |