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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 27288 |
| 5 | 501760 |
| 6 | 12738432 |
| 7 | 182458368 |
| 8 | 1862977116 |
| 9 | 13739292672 |
| 10 | 74852604288 |
| 11 | 306460084224 |
| 12 | 956270217000 |
| 13 | 2294484111360 |
| 14 | 4268285380352 |
| 15 | 6180152832000 |
| 16 | 6991765639110 |
| 17 | 6180152832000 |
| 18 | 4268285380352 |
| 19 | 2294484111360 |
| 20 | 956270217000 |
| 21 | 306460084224 |
| 22 | 74852604288 |
[1,0,0,0,27288,501760,12738432,182458368, 1862977116,13739292672,74852604288,306460084224, 956270217000,2294484111360,4268285380352, 6180152832000,6991765639110,6180152832000, 4268285380352,2294484111360,956270217000, 306460084224,74852604288] |