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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 4 |
| 3 | 16 |
| 4 | 357 |
| 5 | 1880 |
| 6 | 26443 |
| 7 | 1765534 |
| 8 | 25412877 |
| 9 | 1480441810 |
| 10 | 406769105056 |
| 11 | 17832789481005 |
[1,12,4,16,357,1880,26443,1765534,25412877, 1480441810,406769105056,17832789481005] |