n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 2 |
3 | 12 |
4 | 80 |
5 | 630 |
6 | 5816 |
7 | 61978 |
8 | 751222 |
9 | 10225140 |
10 | 154610048 |
11 | 2573280820 |
12 | 46775427860 |
13 | 922374085984 |
14 | 19616567407368 |
15 | 447666534959528 |
16 | 10913339500879576 |
17 | 283081184691349600 |
18 | 7785415448640271232 |
19 | 226306589802176060640 |
20 | 6933002797216545295968 |
[0,0,2,12,80,630,5816,61978,751222,10225140, 154610048,2573280820,46775427860,922374085984, 19616567407368,447666534959528,10913339500879576, 283081184691349600,7785415448640271232, 226306589802176060640,6933002797216545295968] |