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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 64 |
| 4 | 667 |
| 5 | 7526 |
| 6 | 89614 |
| 7 | 1109578 |
| 8 | 14153379 |
| 9 | 184819348 |
| 10 | 2459689862 |
| 11 | 33253032748 |
| 12 | 455530364830 |
| 13 | 6310982029730 |
| 14 | 88288166501864 |
| 15 | 1245647703839594 |
| 16 | 17706547056186467 |
| 17 | 253368343687134676 |
| 18 | 3647065046069378674 |
| 19 | 52777288671194300790 |
| 20 | 767433117054617825162 |
[1,7,64,667,7526,89614,1109578,14153379,184819348, 2459689862,33253032748,455530364830,6310982029730, 88288166501864,1245647703839594,17706547056186467, 253368343687134676,3647065046069378674, 52777288671194300790,767433117054617825162] |