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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 3 |
| 10 | 3 |
| 11 | 7 |
| 12 | 7 |
| 13 | 17 |
| 14 | 17 |
| 15 | 39 |
| 16 | 39 |
| 17 | 127 |
| 18 | 127 |
| 19 | 681 |
| 20 | 681 |
| 21 | 3913 |
| 22 | 3913 |
| 23 | 21369 |
| 24 | 21369 |
| 25 | 147701 |
| 26 | 147701 |
| 27 | 1344439 |
| 28 | 1344439 |
| 29 | 15252227 |
[1,1,1,1,1,1,1,1,3,3,7,7,17,17,39,39,127,127,681, 681,3913,3913,21369,21369,147701,147701,1344439, 1344439,15252227] |