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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 1 |
| 10 | 3 |
| 11 | 5 |
| 12 | 11 |
| 13 | 17 |
| 14 | 33 |
| 15 | 69 |
| 16 | 195 |
| 17 | 461 |
| 18 | 1581 |
| 19 | 4385 |
| 20 | 16401 |
| 21 | 52739 |
| 22 | 234041 |
| 23 | 877033 |
| 24 | 4605425 |
| 25 | 20357297 |
| 26 | 124937647 |
[1,1,1,1,1,1,1,1,1,3,5,11,17,33,69,195,461,1581, 4385,16401,52739,234041,877033,4605425,20357297, 124937647] |