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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 9 |
| 8 | 19 |
| 9 | 59 |
| 10 | 237 |
| 11 | 1193 |
| 12 | 6925 |
| 13 | 46535 |
| 14 | 385115 |
| 15 | 3834729 |
| 16 | 46129325 |
| 17 | 665267927 |
| 18 | 11525172145 |
| 19 | 240724568637 |
| 20 | 6036636466243 |
| 21 | 182136263500283 |
| 22 | 6609883325424453 |
[1,1,1,1,1,3,9,19,59,237,1193,6925,46535,385115, 3834729,46129325,665267927,11525172145, 240724568637,6036636466243,182136263500283, 6609883325424453] |