n | a(n) |
---|---|
1 | 1 |
2 | 6 |
3 | 30 |
4 | 144 |
5 | 687 |
6 | 3296 |
7 | 15972 |
8 | 78294 |
9 | 388320 |
10 | 1947910 |
11 | 9875566 |
12 | 50560246 |
13 | 261177401 |
14 | 1360112590 |
15 | 7134802722 |
16 | 37673830960 |
17 | 200106632766 |
18 | 1068539351340 |
19 | 5733226876876 |
20 | 30894846668416 |
21 | 167137498306038 |
22 | 907416216735816 |
[1,6,30,144,687,3296,15972,78294,388320,1947910, 9875566,50560246,261177401,1360112590,7134802722, 37673830960,200106632766,1068539351340, 5733226876876,30894846668416,167137498306038, 907416216735816] |