n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 1 |
3 | 5 |
4 | 44 |
5 | 244 |
6 | 2064 |
7 | 15168 |
8 | 181824 |
9 | 1878336 |
10 | 21323520 |
11 | 238187520 |
12 | 3496919040 |
13 | 45938949120 |
14 | 699188474880 |
15 | 11185253452800 |
16 | 220809635020800 |
17 | 3774686585241600 |
18 | 75413794524364800 |
19 | 1439264469668659200 |
20 | 31704771803185152000 |
21 | 690129227948654592000 |
[0,0,1,5,44,244,2064,15168,181824,1878336, 21323520,238187520,3496919040,45938949120, 699188474880,11185253452800,220809635020800, 3774686585241600,75413794524364800, 1439264469668659200,31704771803185152000, 690129227948654592000] |