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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 3 |
| 5 | 12 |
| 6 | 24 |
| 7 | 252 |
| 8 | 56 |
| 9 | 18144 |
| 10 | 5184 |
| 11 | 199584 |
| 12 | 33264 |
| 13 | 2395008 |
| 14 | 48384 |
| 15 | 50295168 |
| 16 | 100590336 |
| 17 | 804722688 |
| 18 | 146313216 |
| 19 | 137607579648 |
| 20 | 6552741888 |
| 21 | 11559036690432 |
| 22 | 1216740704256 |
| 23 | 2924436282679296 |
| 24 | 835553223622656 |
| 25 | 70186470784303104 |
| 26 | 226043384168448 |
| 27 | 1895034711176183808 |
[1,2,3,3,12,24,252,56,18144,5184,199584,33264, 2395008,48384,50295168,100590336,804722688, 146313216,137607579648,6552741888,11559036690432, 1216740704256,2924436282679296,835553223622656, 70186470784303104,226043384168448, 1895034711176183808] |