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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 6 |
| 3 | 112 |
| 4 | 6664 |
| 5 | 1270016 |
| 6 | 776239200 |
| 7 | 1522266730496 |
| 8 | 9580300901941376 |
| 9 | 193509323594243571712 |
| 10 | 12545297912843041612924416 |
| 11 | 2610531939025273190037188509696 |
| 12 | 1743627211475190637398673259679582208 |
[1,1,6,112,6664,1270016,776239200,1522266730496, 9580300901941376,193509323594243571712, 12545297912843041612924416, 2610531939025273190037188509696, 1743627211475190637398673259679582208] |