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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 17 |
| 2 | 101 |
| 3 | 623 |
| 4 | 3953 |
| 5 | 25607 |
| 6 | 168401 |
| 7 | 1119863 |
| 8 | 7509953 |
| 9 | 50693447 |
| 10 | 343990001 |
| 11 | 2344318103 |
| 12 | 16034846753 |
| 13 | 110016813287 |
| 14 | 756855672401 |
| 15 | 5218820236343 |
| 16 | 36058335444353 |
| 17 | 249574353301127 |
| 18 | 1730042274055601 |
| 19 | 12008529803290583 |
[3,17,101,623,3953,25607,168401,1119863,7509953, 50693447,343990001,2344318103,16034846753, 110016813287,756855672401,5218820236343, 36058335444353,249574353301127,1730042274055601, 12008529803290583] |