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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 3 |
| 9 | 9 |
| 10 | 19 |
| 11 | 33 |
| 12 | 65 |
| 13 | 207 |
| 14 | 775 |
| 15 | 3377 |
| 16 | 13307 |
| 17 | 53409 |
| 18 | 249201 |
| 19 | 1453605 |
| 20 | 9533963 |
| 21 | 70032903 |
| 22 | 523853865 |
| 23 | 4420682653 |
[1,1,1,1,1,1,1,3,9,19,33,65,207,775,3377,13307, 53409,249201,1453605,9533963,70032903,523853865, 4420682653] |