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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 11 |
| 4 | 96 |
| 5 | 1149 |
| 6 | 17520 |
| 7 | 324855 |
| 8 | 7096320 |
| 9 | 178495065 |
| 10 | 5081045760 |
| 11 | 161485639875 |
| 12 | 5668185600000 |
| 13 | 217773547039125 |
| 14 | 9090267234048000 |
| 15 | 409648199646660975 |
| 16 | 19822083757572096000 |
| 17 | 1025047834112461784625 |
| 18 | 56415976360602034176000 |
| 19 | 3292602426688307236378875 |
[1,2,11,96,1149,17520,324855,7096320,178495065, 5081045760,161485639875,5668185600000, 217773547039125,9090267234048000, 409648199646660975,19822083757572096000, 1025047834112461784625,56415976360602034176000, 3292602426688307236378875] |