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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 421 |
| 4 | 1541 |
| 5 | 8753 |
| 6 | 150421 |
| 7 | 12914246 |
| 8 | 1327696379533 |
| 9 | 4034385661121 |
| 10 | 605166395826533 |
| 11 | 16360402306368458 |
| 12 | 249752330575267378 |
[1,2,421,1541,8753,150421,12914246,1327696379533, 4034385661121,605166395826533,16360402306368458, 249752330575267378] |