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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 10 |
| 4 | 102 |
| 5 | 1578 |
| 6 | 32920 |
| 7 | 864813 |
| 8 | 27405798 |
| 9 | 1017153322 |
| 10 | 43271534196 |
| 11 | 2075757894648 |
| 12 | 110845691264880 |
| 13 | 6521081183455941 |
| 14 | 419050045344986432 |
| 15 | 29204306270878653424 |
| 16 | 2193909534863339799870 |
| 17 | 176728502294889963614250 |
[1,2,10,102,1578,32920,864813,27405798,1017153322, 43271534196,2075757894648,110845691264880, 6521081183455941,419050045344986432, 29204306270878653424,2193909534863339799870, 176728502294889963614250] |