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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 5 |
| 5 | 9 |
| 6 | 12 |
| 7 | 15 |
| 8 | 21 |
| 9 | 264 |
| 10 | 383 |
| 11 | 2720 |
| 12 | 4494 |
| 13 | 21167 |
| 14 | 45825 |
| 15 | 55851 |
| 16 | 64568 |
| 17 | 70727 |
[1,2,3,5,9,12,15,21,264,383,2720,4494,21167,45825, 55851,64568,70727] |