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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 8 |
| 4 | 88 |
| 5 | 252 |
| 6 | 2772 |
| 7 | 29792 |
| 8 | 2112 |
| 9 | 4224 |
| 10 | 8448 |
| 11 | 489984 |
| 12 | 48384 |
| 13 | 2977792 |
| 14 | 8634368 |
| 15 | 405504 |
| 16 | 40955904 |
| 17 | 405909504 |
| 18 | 23080108032 |
| 19 | 25135153152 |
| 20 | 677707776 |
| 21 | 2557800087552 |
| 22 | 21128282112 |
| 23 | 633498894336 |
| 24 | 23255666655232 |
| 25 | 8691508051968 |
| 26 | 29142024192 |
| 27 | 65892155129856 |
| 28 | 4815463645184 |
[1,2,4,8,88,252,2772,29792,2112,4224,8448,489984, 48384,2977792,8634368,405504,40955904,405909504, 23080108032,25135153152,677707776,2557800087552, 21128282112,633498894336,23255666655232, 8691508051968,29142024192,65892155129856, 4815463645184] |