n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 0 |
3 | 0 |
4 | 4 |
5 | 16 |
6 | 80 |
7 | 672 |
8 | 4896 |
9 | 49920 |
10 | 460032 |
11 | 5598720 |
12 | 62584320 |
13 | 885381120 |
14 | 11644323840 |
15 | 187811205120 |
16 | 2841958748160 |
17 | 51481298534400 |
18 | 881192033648640 |
19 | 17714783352913920 |
20 | 338434210452602880 |
21 | 7477275543168614400 |
[1,0,0,0,4,16,80,672,4896,49920,460032,5598720, 62584320,885381120,11644323840,187811205120, 2841958748160,51481298534400,881192033648640, 17714783352913920,338434210452602880, 7477275543168614400] |