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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 7 |
| 4 | 0 |
| 5 | 2521 |
| 6 | 20161 |
| 7 | 604801 |
| 8 | 6652801 |
| 9 | 726485761 |
| 10 | 39916801 |
| 11 | 39916801 |
| 12 | 140792940288001 |
| 13 | 14820309504001 |
| 14 | 10461394944001 |
| 15 | 641171050071552001 |
| 16 | 425757851430912001 |
| 17 | 9366672731480064001 |
| 18 | 8515157028618240001 |
[2,3,7,0,2521,20161,604801,6652801,726485761, 39916801,39916801,140792940288001,14820309504001, 10461394944001,641171050071552001, 425757851430912001,9366672731480064001, 8515157028618240001] |