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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 6 |
| 2 | 12 |
| 3 | 36 |
| 4 | 180 |
| 5 | 1620 |
| 6 | 27540 |
| 7 | 908820 |
| 8 | 59073300 |
| 9 | 7620455700 |
| 10 | 1958457114900 |
| 11 | 1004688499943700 |
| 12 | 1029805712442292500 |
| 13 | 2110071904794257332500 |
| 14 | 8644964593942072291252500 |
| 15 | 70828194918167398282231732500 |
[4,6,12,36,180,1620,27540,908820,59073300, 7620455700,1958457114900,1004688499943700, 1029805712442292500,2110071904794257332500, 8644964593942072291252500, 70828194918167398282231732500] |