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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 25 |
| 7 | 0 |
| 8 | 738 |
| 9 | 5120 |
| 10 | 40908 |
| 11 | 0 |
| 12 | 3662892 |
| 13 | 0 |
| 14 | 482141160 |
| 15 | 6261884552 |
| 16 | 87600164760 |
| 17 | 0 |
| 18 | 21000656701120 |
| 19 | 0 |
| 20 | 6421274296759014 |
| 21 | 121967975910086640 |
| 22 | 2438739530264419200 |
| 23 | 0 |
| 24 | 1126236239013683565846 |
| 25 | 25899122858782713781248 |
[1,0,0,0,0,25,0,738,5120,40908,0,3662892,0, 482141160,6261884552,87600164760,0,21000656701120, 0,6421274296759014,121967975910086640, 2438739530264419200,0,1126236239013683565846, 25899122858782713781248] |