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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 3 |
| 8 | 19 |
| 9 | 43 |
| 10 | 71 |
| 11 | 159 |
| 12 | 607 |
| 13 | 2057 |
| 14 | 8951 |
| 15 | 43111 |
| 16 | 227107 |
| 17 | 1266527 |
| 18 | 7483327 |
| 19 | 50232185 |
| 20 | 389882233 |
| 21 | 3353662007 |
[1,1,1,1,1,1,3,19,43,71,159,607,2057,8951,43111, 227107,1266527,7483327,50232185,389882233, 3353662007] |