n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 3 |
4 | 6 |
5 | 30 |
6 | 300 |
7 | 2100 |
8 | 11760 |
9 | 105840 |
10 | 1421280 |
11 | 15634080 |
12 | 147692160 |
13 | 1919998080 |
14 | 33106993920 |
15 | 496604908800 |
16 | 6638004172800 |
17 | 112846070937600 |
18 | 2386916704972800 |
19 | 45351417394483200 |
20 | 785383247480832000 |
21 | 16493048197097472000 |
22 | 413938002507853824000 |
[0,1,3,6,30,300,2100,11760,105840,1421280, 15634080,147692160,1919998080,33106993920, 496604908800,6638004172800,112846070937600, 2386916704972800,45351417394483200, 785383247480832000,16493048197097472000, 413938002507853824000] |