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| n | a(n) |
|---|---|
| 10 | 1 |
| 11 | 44 |
| 12 | 1128 |
| 13 | 22100 |
| 14 | 367290 |
| 15 | 5461512 |
| 16 | 74974368 |
| 17 | 969443904 |
| 18 | 11969016345 |
| 19 | 142466675900 |
| 20 | 1646492110120 |
| 21 | 18574174153080 |
| 22 | 205371886988268 |
| 23 | 2232785266876080 |
| 24 | 23929614612052080 |
| 25 | 253338471349988640 |
[1,44,1128,22100,367290,5461512,74974368, 969443904,11969016345,142466675900,1646492110120, 18574174153080,205371886988268,2232785266876080, 23929614612052080,253338471349988640] |