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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 13 |
| 4 | 101 |
| 5 | 1356 |
| 6 | 44148 |
| 7 | 3241470 |
| 8 | 456790733 |
| 9 | 132506438551 |
| 10 | 79120923192740 |
[0,2,13,101,1356,44148,3241470,456790733, 132506438551,79120923192740] |