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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 6 |
| 4 | 12 |
| 5 | 60 |
| 6 | 180 |
| 7 | 1260 |
| 8 | 2760 |
| 9 | 7560 |
| 10 | 37800 |
| 11 | 415800 |
| 12 | 1265040 |
| 13 | 16287864 |
| 14 | 113538360 |
| 15 | 567638664 |
| 16 | 1135134000 |
| 17 | 19298936664 |
| 18 | 58868650320 |
| 19 | 1113894381120 |
| 20 | 5499724230000 |
| 21 | 39112247205360 |
| 22 | 423754918508832 |
| 23 | 10054207233388032 |
| 24 | 29220034833990000 |
| 25 | 146100190526456640 |
| 26 | 1915895635570469280 |
| 27 | 5712343370808883200 |
| 28 | 39885667247556843120 |
[1,6,12,60,180,1260,2760,7560,37800,415800, 1265040,16287864,113538360,567638664,1135134000, 19298936664,58868650320,1113894381120, 5499724230000,39112247205360,423754918508832, 10054207233388032,29220034833990000, 146100190526456640,1915895635570469280, 5712343370808883200,39885667247556843120] |