n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 2 |
3 | 0 |
4 | 24 |
5 | 120 |
6 | 1440 |
7 | 15120 |
8 | 201600 |
9 | 2903040 |
10 | 47174400 |
11 | 838252800 |
12 | 16286054400 |
13 | 342486144000 |
14 | 7758867916800 |
15 | 188305108992000 |
16 | 4875010043904000 |
17 | 134094160392192000 |
18 | 3905447960494080000 |
[0,0,2,0,24,120,1440,15120,201600,2903040, 47174400,838252800,16286054400,342486144000, 7758867916800,188305108992000,4875010043904000, 134094160392192000,3905447960494080000] |