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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 149 |
| 8 | 307 |
| 9 | 3283 |
| 10 | 9637 |
| 11 | 237685 |
| 12 | 792401 |
| 13 | 149008323 |
| 14 | 690862749 |
| 15 | 219427051049 |
| 16 | 1350088886833 |
| 17 | 717485827831517 |
| 18 | 5812692511149509 |
| 19 | 9087725403509413361 |
| 20 | 98388300257852844757 |
| 21 | 382960435361198474272451 |
[1,1,1,1,1,1,149,307,3283,9637,237685,792401, 149008323,690862749,219427051049,1350088886833, 717485827831517,5812692511149509, 9087725403509413361,98388300257852844757, 382960435361198474272451] |