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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 40 |
| 3 | 1800 |
| 4 | 149024 |
| 5 | 21223800 |
| 6 | 4609532520 |
| 7 | 1414165715200 |
| 8 | 581109518753920 |
| 9 | 307788983933760954 |
| 10 | 204081628466048180200 |
| 11 | 165541724073121026987224 |
| 12 | 161233041454793035411134240 |
| 13 | 185663865439487951708529417080 |
| 14 | 249499302292252719726304186789160 |
[1,2,40,1800,149024,21223800,4609532520, 1414165715200,581109518753920,307788983933760954, 204081628466048180200,165541724073121026987224, 161233041454793035411134240, 185663865439487951708529417080, 249499302292252719726304186789160] |