n | a(n) |
---|---|
0 | 1 |
1 | 20 |
2 | 210 |
3 | 1680 |
4 | 11550 |
5 | 72072 |
6 | 420420 |
7 | 2333760 |
8 | 12471030 |
9 | 64664600 |
10 | 327202876 |
11 | 1622493600 |
12 | 7909656300 |
13 | 38003792400 |
14 | 180324117000 |
15 | 846321189120 |
16 | 3934071152550 |
17 | 18132120329400 |
18 | 82937661506700 |
[1,20,210,1680,11550,72072,420420,2333760, 12471030,64664600,327202876,1622493600,7909656300, 38003792400,180324117000,846321189120, 3934071152550,18132120329400,82937661506700] |