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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 104 |
| 4 | 1870 |
| 5 | 51632 |
| 6 | 2027470 |
| 7 | 107354144 |
| 8 | 7370645950 |
| 9 | 636754087472 |
| 10 | 67591284235630 |
| 11 | 8647294709864384 |
| 12 | 1312197219579059230 |
| 13 | 233025643830843282512 |
[1,2,10,104,1870,51632,2027470,107354144, 7370645950,636754087472,67591284235630, 8647294709864384,1312197219579059230, 233025643830843282512] |