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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 33 |
| 3 | 257 |
| 4 | 2571 |
| 5 | 19603 |
| 6 | 159463 |
| 7 | 1353761 |
| 8 | 11871747 |
| 9 | 99322949 |
| 10 | 832736311 |
| 11 | 7100237801 |
| 12 | 60485596877 |
| 13 | 511509684117 |
| 14 | 4330650440271 |
| 15 | 36779000662959 |
| 16 | 312087013491651 |
| 17 | 2645221650088423 |
| 18 | 22429333082583617 |
| 19 | 190276664212068839 |
[1,33,257,2571,19603,159463,1353761,11871747, 99322949,832736311,7100237801,60485596877, 511509684117,4330650440271,36779000662959, 312087013491651,2645221650088423, 22429333082583617,190276664212068839] |