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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 16 |
| 5 | 100 |
| 6 | 72 |
| 7 | 1764 |
| 8 | 768 |
| 9 | 39852 |
| 10 | 14400 |
| 11 | 1222100 |
| 12 | 277632 |
| 13 | 47179392 |
| 14 | 8754144 |
| 15 | 2319055200 |
[1,2,6,16,100,72,1764,768,39852,14400,1222100, 277632,47179392,8754144,2319055200] |