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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 16 |
| 3 | 1208 |
| 4 | 1383936 |
| 5 | 32718467072 |
| 6 | 20166949856488576 |
| 7 | 391322675415566237681536 |
[1,2,16,1208,1383936,32718467072, 20166949856488576,391322675415566237681536] |