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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 36 |
| 4 | 192 |
| 5 | 1992 |
| 6 | 2016 |
| 7 | 31067664 |
| 8 | 39206496 |
| 9 | 1564356432 |
| 10 | 3937403136 |
| 11 | 15600000432 |
| 12 | 22871605008 |
| 13 | 156043560432 |
| 14 | 156439956432 |
| 15 | 1560000000432 |
| 16 | 1956000004392 |
[1,12,36,192,1992,2016,31067664,39206496, 1564356432,3937403136,15600000432,22871605008, 156043560432,156439956432,1560000000432, 1956000004392] |