n | a(n) |
---|---|
1 | 0 |
2 | 2 |
3 | 12 |
4 | 72 |
5 | 480 |
6 | 3600 |
7 | 30240 |
8 | 282240 |
9 | 2903040 |
10 | 32659200 |
11 | 399168000 |
12 | 5269017600 |
13 | 74724249600 |
14 | 1133317785600 |
15 | 18307441152000 |
16 | 313841848320000 |
17 | 5690998849536000 |
18 | 108840352997376000 |
19 | 2189611807358976000 |
20 | 46225138155356160000 |
21 | 1021818843434188800000 |
[0,2,12,72,480,3600,30240,282240,2903040,32659200, 399168000,5269017600,74724249600,1133317785600, 18307441152000,313841848320000,5690998849536000, 108840352997376000,2189611807358976000, 46225138155356160000,1021818843434188800000] |