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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 4 |
| 3 | 12 |
| 4 | 32 |
| 5 | 120 |
| 6 | 288 |
| 7 | 1512 |
| 8 | 4096 |
| 9 | 15552 |
| 10 | 48000 |
| 11 | 240064 |
| 12 | 552960 |
| 13 | 3439800 |
| 14 | 9483264 |
| 15 | 35640000 |
| 16 | 134217728 |
| 17 | 673699800 |
| 18 | 1451188224 |
| 19 | 9644765256 |
| 20 | 23685120000 |
| 21 | 115605729792 |
| 22 | 401556013056 |
| 23 | 1996264531840 |
| 24 | 4566087106560 |
| 25 | 26244000000000 |
| 26 | 89961392102400 |
| 27 | 356237685227520 |
[1,2,4,12,32,120,288,1512,4096,15552,48000,240064, 552960,3439800,9483264,35640000,134217728, 673699800,1451188224,9644765256,23685120000, 115605729792,401556013056,1996264531840, 4566087106560,26244000000000,89961392102400, 356237685227520] |