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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 57 |
| 5 | 397 |
| 6 | 3487 |
| 7 | 37519 |
| 8 | 484437 |
| 9 | 7353473 |
| 10 | 129104523 |
| 11 | 2589967603 |
| 12 | 58757627185 |
| 13 | 1493762354293 |
| 14 | 42223299711159 |
| 15 | 1318186323111959 |
| 16 | 45185985199663629 |
| 17 | 1691822823829309801 |
| 18 | 68865092213424362659 |
| 19 | 3034735030143197197435 |
| 20 | 144238580771432519823465 |
| 21 | 7368717925255301486594525 |
[1,3,11,57,397,3487,37519,484437,7353473, 129104523,2589967603,58757627185,1493762354293, 42223299711159,1318186323111959,45185985199663629, 1691822823829309801,68865092213424362659, 3034735030143197197435,144238580771432519823465, 7368717925255301486594525] |