n | a(n) |
---|---|
1 | 0 |
2 | 2 |
3 | 18 |
4 | 72 |
5 | 300 |
6 | 1440 |
7 | 7056 |
8 | 39312 |
9 | 252720 |
10 | 1658880 |
11 | 10349856 |
12 | 62099136 |
13 | 367960320 |
14 | 2179768320 |
15 | 12976433280 |
16 | 77787495936 |
17 | 468419708160 |
18 | 2821539889152 |
19 | 16960580969472 |
20 | 101753146100736 |
21 | 609923828966400 |
22 | 3656096522698752 |
23 | 21926115464435712 |
24 | 131556692786614272 |
[0,2,18,72,300,1440,7056,39312,252720,1658880, 10349856,62099136,367960320,2179768320, 12976433280,77787495936,468419708160, 2821539889152,16960580969472,101753146100736, 609923828966400,3656096522698752, 21926115464435712,131556692786614272] |