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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 56 |
| 4 | 360 |
| 5 | 992 |
| 6 | 2016 |
| 7 | 16256 |
| 8 | 120960 |
| 9 | 131040 |
| 10 | 1571328 |
| 11 | 8714160 |
| 12 | 67100672 |
| 13 | 94279680 |
| 14 | 182131200 |
| 15 | 571963392 |
| 16 | 1379454720 |
| 17 | 4428914688 |
| 18 | 5517818880 |
| 19 | 17179738112 |
| 20 | 70912195200 |
| 21 | 153003540480 |
| 22 | 159991977600 |
| 23 | 175445913600 |
| 24 | 265734881280 |
| 25 | 274877382656 |
| 26 | 612014161920 |
[1,12,56,360,992,2016,16256,120960,131040,1571328, 8714160,67100672,94279680,182131200,571963392, 1379454720,4428914688,5517818880,17179738112, 70912195200,153003540480,159991977600, 175445913600,265734881280,274877382656, 612014161920] |