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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 0 |
| 8 | 0 |
| 9 | 0 |
| 10 | 2 |
| 11 | 160 |
| 12 | 6056 |
| 13 | 161136 |
| 14 | 3661824 |
| 15 | 76972416 |
| 16 | 1572313392 |
| 17 | 32096768008 |
| 18 | 665456850864 |
| 19 | 14144815265510 |
| 20 | 309931658271656 |
[1,1,0,0,0,0,0,0,0,0,2,160,6056,161136,3661824, 76972416,1572313392,32096768008,665456850864, 14144815265510,309931658271656] |