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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 9 |
| 3 | 105 |
| 4 | 7665 |
| 5 | 303345 |
| 6 | 25893945 |
| 7 | 1765268505 |
| 8 | 345763843425 |
| 9 | 42813526781025 |
| 10 | 9399638261838825 |
| 11 | 1573582072888650825 |
| 12 | 563295733721953657425 |
| 13 | 139523356060051359020625 |
| 14 | 55722660999371761475705625 |
| 15 | 17053184982967015188566885625 |
| 16 | 9496879931794641573011009810625 |
[1,1,9,105,7665,303345,25893945,1765268505, 345763843425,42813526781025,9399638261838825, 1573582072888650825,563295733721953657425, 139523356060051359020625, 55722660999371761475705625, 17053184982967015188566885625, 9496879931794641573011009810625] |