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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 160 |
| 3 | 896 |
| 4 | 18432 |
| 5 | 90112 |
| 6 | 851968 |
| 7 | 1310720 |
| 8 | 142606336 |
| 9 | 637534208 |
| 10 | 5637144576 |
| 11 | 24696061952 |
| 12 | 429496729600 |
| 13 | 1855425871872 |
| 14 | 15942918602752 |
| 15 | 68169720922112 |
| 16 | 1548112371908608 |
| 17 | 3940649673949184 |
| 18 | 166633186212708352 |
[1,12,160,896,18432,90112,851968,1310720, 142606336,637534208,5637144576,24696061952, 429496729600,1855425871872,15942918602752, 68169720922112,1548112371908608,3940649673949184, 166633186212708352] |