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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 4 |
| 7 | 19 |
| 8 | 21 |
| 9 | 28 |
| 10 | 151 |
| 11 | 200 |
| 12 | 709 |
| 13 | 767 |
| 14 | 5727 |
| 15 | 15908 |
| 16 | 162819 |
| 17 | 302991 |
[1,1,1,1,2,4,19,21,28,151,200,709,767,5727,15908, 162819,302991] |