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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 60 |
| 3 | 660 |
| 4 | 3597 |
| 5 | 78480 |
| 6 | 856080 |
| 7 | 4669203 |
| 8 | 101866380 |
| 9 | 1111191780 |
| 10 | 6060621597 |
| 11 | 132222483360 |
| 12 | 1442326073760 |
| 13 | 7866682164003 |
| 14 | 171624681534300 |
| 15 | 1872138132549300 |
| 16 | 10210947388253997 |
| 17 | 222768704409038640 |
| 18 | 2430033853722917040 |
[3,60,660,3597,78480,856080,4669203,101866380, 1111191780,6060621597,132222483360,1442326073760, 7866682164003,171624681534300,1872138132549300, 10210947388253997,222768704409038640, 2430033853722917040] |