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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 12 |
| 4 | 48 |
| 5 | 80 |
| 6 | 360 |
| 7 | 1344 |
| 8 | 2688 |
| 9 | 8640 |
| 10 | 51840 |
| 11 | 63360 |
| 12 | 443520 |
| 13 | 1198080 |
| 14 | 2515968 |
| 15 | 10886400 |
| 16 | 48384000 |
| 17 | 87736320 |
| 18 | 465315840 |
| 19 | 1134673920 |
| 20 | 3309465600 |
| 21 | 11887948800 |
| 22 | 71530905600 |
| 23 | 78343372800 |
| 24 | 528817766400 |
| 25 | 1839366144000 |
| 26 | 3260694528000 |
| 27 | 15837659136000 |
| 28 | 82169502105600 |
[1,2,4,12,48,80,360,1344,2688,8640,51840,63360, 443520,1198080,2515968,10886400,48384000,87736320, 465315840,1134673920,3309465600,11887948800, 71530905600,78343372800,528817766400, 1839366144000,3260694528000,15837659136000, 82169502105600] |