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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 100 |
| 3 | 368 |
| 4 | 1696 |
| 5 | 6656 |
| 6 | 27520 |
| 7 | 109568 |
| 8 | 441856 |
| 9 | 1765376 |
| 10 | 7075840 |
| 11 | 28295168 |
| 12 | 113238016 |
| 13 | 452919296 |
| 14 | 1811906560 |
| 15 | 7247495168 |
| 16 | 28990898176 |
| 17 | 115963068416 |
| 18 | 463855943680 |
| 19 | 1855421677568 |
| 20 | 7421701390336 |
| 21 | 29686797172736 |
[1,11,100,368,1696,6656,27520,109568,441856, 1765376,7075840,28295168,113238016,452919296, 1811906560,7247495168,28990898176,115963068416, 463855943680,1855421677568,7421701390336, 29686797172736] |