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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 3 |
| 6 | 7 |
| 7 | 69 |
| 8 | 574 |
| 9 | 3336 |
| 10 | 23562 |
| 11 | 140933 |
| 12 | 948340 |
| 13 | 5733551 |
| 14 | 37091416 |
| 15 | 225775799 |
| 16 | 1419329282 |
| 17 | 8589008422 |
[1,1,1,1,3,7,69,574,3336,23562,140933,948340, 5733551,37091416,225775799,1419329282,8589008422] |