n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 1 |
4 | 2 |
5 | 4 |
6 | 12 |
7 | 48 |
8 | 240 |
9 | 1680 |
10 | 15120 |
11 | 181440 |
12 | 2903040 |
13 | 60963840 |
14 | 1706987520 |
15 | 63158538240 |
16 | 3094768373760 |
17 | 201159944294400 |
18 | 17299755209318400 |
19 | 1972172093862297600 |
20 | 297797986173206937600 |
21 | 59559597234641387520000 |
[1,1,1,2,4,12,48,240,1680,15120,181440,2903040, 60963840,1706987520,63158538240,3094768373760, 201159944294400,17299755209318400, 1972172093862297600,297797986173206937600, 59559597234641387520000] |