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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 15 |
| 7 | 1085 |
| 8 | 216230 |
| 9 | 92550276 |
| 10 | 74358276300 |
| 11 | 102660061574400 |
| 12 | 228311514581611725 |
| 13 | 777903709095959606875 |
| 14 | 3900045557544532389044051 |
| 15 | 27829438251904221299882526375 |
| 16 | 274842860343937013061411903607000 |
| 17 | 3668195394384971166861021308091920000 |
[0,0,0,1,1,15,1085,216230,92550276,74358276300, 102660061574400,228311514581611725, 777903709095959606875,3900045557544532389044051, 27829438251904221299882526375, 274842860343937013061411903607000, 3668195394384971166861021308091920000] |