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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 7 |
| 2 | 127 |
| 3 | 1518 |
| 4 | 15800 |
| 5 | 154410 |
| 6 | 1470702 |
| 7 | 13921922 |
| 8 | 132465058 |
| 9 | 1275540777 |
| 10 | 12482994680 |
| 11 | 124488408308 |
| 12 | 1267192059423 |
| 13 | 13179257452283 |
| 14 | 140124528853582 |
| 15 | 1523425278785190 |
| 16 | 16936782395913056 |
| 17 | 192530701636263004 |
| 18 | 2237390160167413881 |
| 19 | 26572938927762778750 |
[0,7,127,1518,15800,154410,1470702,13921922, 132465058,1275540777,12482994680,124488408308, 1267192059423,13179257452283,140124528853582, 1523425278785190,16936782395913056, 192530701636263004,2237390160167413881, 26572938927762778750] |