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| n | a(n) |
|---|---|
| 1 | 512 |
| 2 | 2703 |
| 3 | 12730 |
| 4 | 55904 |
| 5 | 221858 |
| 6 | 833037 |
| 7 | 2977462 |
| 8 | 10225464 |
| 9 | 34028886 |
| 10 | 110280168 |
| 11 | 349551666 |
| 12 | 1087417895 |
| 13 | 3328908758 |
| 14 | 10051170955 |
| 15 | 29985882752 |
| 16 | 88525404974 |
| 17 | 258951023734 |
| 18 | 751340000125 |
| 19 | 2164314393804 |
| 20 | 6194580296317 |
| 21 | 17628054712962 |
[512,2703,12730,55904,221858,833037,2977462, 10225464,34028886,110280168,349551666,1087417895, 3328908758,10051170955,29985882752,88525404974, 258951023734,751340000125,2164314393804, 6194580296317,17628054712962] |