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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 3 |
| 5 | 20 |
| 6 | 2 |
| 7 | 35 |
| 8 | 455 |
| 9 | 5804 |
| 10 | 73232 |
| 11 | 6 |
| 12 | 167 |
| 13 | 2001 |
| 14 | 24974 |
| 15 | 339220 |
| 16 | 4646117 |
| 17 | 65758725 |
[1,1,1,3,20,2,35,455,5804,73232,6,167,2001,24974, 339220,4646117,65758725] |