n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 2 |
3 | 6 |
4 | 36 |
5 | 240 |
6 | 1800 |
7 | 16800 |
8 | 178080 |
9 | 2086560 |
10 | 27518400 |
11 | 399168000 |
12 | 6286896000 |
13 | 107623676160 |
14 | 1984274772480 |
15 | 39143052748800 |
16 | 824445099878400 |
17 | 18450791322163200 |
18 | 437015358530150400 |
19 | 10929450232744243200 |
20 | 287728555881102336000 |
21 | 7952251084537503744000 |
[1,1,2,6,36,240,1800,16800,178080,2086560, 27518400,399168000,6286896000,107623676160, 1984274772480,39143052748800,824445099878400, 18450791322163200,437015358530150400, 10929450232744243200,287728555881102336000, 7952251084537503744000] |