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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 17 |
| 5 | 53 |
| 6 | 329 |
| 7 | 3195 |
| 8 | 60697 |
| 9 | 1822001 |
| 10 | 62512113 |
| 11 | 3196151109 |
| 12 | 269695770307 |
| 13 | 35398633644551 |
[1,1,1,17,53,329,3195,60697,1822001,62512113, 3196151109,269695770307,35398633644551] |