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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 10 |
| 3 | 264 |
| 4 | 33864 |
| 5 | 19158720 |
| 6 | 44680224960 |
| 7 | 413586858182400 |
| 8 | 14960200449325582080 |
| 9 | 2109063823453947981680640 |
| 10 | 1162864344149083760773678387200 |
| 11 | 2520991223487759548686737154649702400 |
| 12 | 21598422878151131130336454273775859841843200 |
| 13 | 734233037731110118818452425552296701963294284185600 |
[1,2,10,264,33864,19158720,44680224960, 413586858182400,14960200449325582080, 2109063823453947981680640, 1162864344149083760773678387200, 2520991223487759548686737154649702400, 21598422878151131130336454273775859841843200, 73423303773111011881845242555229670196329428418560\ 0] |