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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 12 |
| 5 | 0 |
| 6 | 1 |
| 7 | 420 |
| 8 | 120 |
| 9 | 0 |
| 10 | 1 |
| 11 | 10248 |
| 12 | 36400 |
| 13 | 896 |
| 14 | 0 |
| 15 | 1 |
| 16 | 196920 |
| 17 | 4858560 |
| 18 | 2170560 |
| 19 | 5760 |
| 20 | 0 |
| 21 | 1 |
| 22 | 3247860 |
| 23 | 461126160 |
| 24 | 1127738304 |
| 25 | 102960000 |
| 26 | 33792 |
| 27 | 0 |
| 28 | 1 |
| 29 | 48361404 |
| 30 | 35248293080 |
| 31 | 340884800256 |
| 32 | 187282263168 |
| 33 | 4083183104 |
| 34 | 186368 |
| 35 | 0 |
| 36 | 1 |
| 37 | 669616080 |
| 38 | 2290777550880 |
| 39 | 76526954183680 |
| 40 | 153279541958400 |
| 41 | 25081621813248 |
| 42 | 141360128000 |
| 43 | 983040 |
| 44 | 0 |
[1,1,0,1,12,0,1,420,120,0,1,10248,36400,896,0,1, 196920,4858560,2170560,5760,0,1,3247860,461126160, 1127738304,102960000,33792,0,1,48361404, 35248293080,340884800256,187282263168,4083183104, 186368,0,1,669616080,2290777550880,76526954183680, 153279541958400,25081621813248,141360128000, 983040,0] |