n | a(n) |
---|---|
0 | 1 |
1 | 3 |
2 | 20 |
3 | 140 |
4 | 1008 |
5 | 7392 |
6 | 54912 |
7 | 411840 |
8 | 3111680 |
9 | 23648768 |
10 | 180590592 |
11 | 1384527872 |
12 | 10650214400 |
13 | 82158796800 |
14 | 635361361920 |
15 | 4924050554880 |
16 | 38233804308480 |
17 | 297374033510400 |
18 | 2316387208396800 |
19 | 18067820225495040 |
20 | 141101072237199360 |
21 | 1103153837490831360 |
[1,3,20,140,1008,7392,54912,411840,3111680, 23648768,180590592,1384527872,10650214400, 82158796800,635361361920,4924050554880, 38233804308480,297374033510400,2316387208396800, 18067820225495040,141101072237199360, 1103153837490831360] |