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| n | a(n) |
|---|---|
| 1 | 55 |
| 2 | 1536 |
| 3 | 1944 |
| 4 | 4056 |
| 5 | 9600 |
| 6 | 24576 |
| 7 | 55296 |
| 8 | 124416 |
| 9 | 279936 |
| 10 | 645504 |
| 11 | 1476096 |
| 12 | 3393024 |
| 13 | 7742976 |
| 14 | 17750400 |
| 15 | 40560000 |
| 16 | 92952576 |
| 17 | 212557824 |
| 18 | 486864384 |
| 19 | 1113680256 |
| 20 | 2550116736 |
| 21 | 5834651136 |
| 22 | 13357979136 |
| 23 | 30567200256 |
| 24 | 69973632384 |
| 25 | 160134620544 |
[55,1536,1944,4056,9600,24576,55296,124416,279936, 645504,1476096,3393024,7742976,17750400,40560000, 92952576,212557824,486864384,1113680256, 2550116736,5834651136,13357979136,30567200256, 69973632384,160134620544] |