n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 1 |
3 | 3 |
4 | 20 |
5 | 220 |
6 | 3648 |
7 | 84616 |
8 | 2617696 |
9 | 104112576 |
10 | 5176135040 |
11 | 314525766016 |
12 | 22934467613184 |
13 | 1976385358538240 |
14 | 198701625441195520 |
15 | 23050434113386398720 |
16 | 3055967615464202301440 |
17 | 459172688072604359835648 |
18 | 77616824553405653653094400 |
[1,1,1,3,20,220,3648,84616,2617696,104112576, 5176135040,314525766016,22934467613184, 1976385358538240,198701625441195520, 23050434113386398720,3055967615464202301440, 459172688072604359835648, 77616824553405653653094400] |