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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 42 |
| 4 | 176 |
| 5 | 1656 |
| 6 | 25535 |
| 7 | 536768 |
| 8 | 14123143 |
| 9 | 595925622 |
| 10 | 38030336629 |
| 11 | 3481512865400 |
| 12 | 454136719811653 |
| 13 | 87600895347244742 |
[1,2,8,42,176,1656,25535,536768,14123143, 595925622,38030336629,3481512865400, 454136719811653,87600895347244742] |