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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 1 |
| 9 | 5 |
| 10 | 5 |
| 11 | 19 |
| 12 | 19 |
| 13 | 89 |
| 14 | 89 |
| 15 | 531 |
| 16 | 531 |
| 17 | 4899 |
| 18 | 4899 |
| 19 | 96559 |
| 20 | 96559 |
| 21 | 2300395 |
| 22 | 2300395 |
| 23 | 69316227 |
| 24 | 69316227 |
| 25 | 2985544439 |
| 26 | 2985544439 |
[1,1,1,1,1,1,1,1,5,5,19,19,89,89,531,531,4899, 4899,96559,96559,2300395,2300395,69316227, 69316227,2985544439,2985544439] |