n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 40 |
3 | 544 |
4 | 8536 |
5 | 145504 |
6 | 2618176 |
7 | 48943360 |
8 | 941244376 |
9 | 18502137184 |
10 | 370091343040 |
11 | 7508629231360 |
12 | 154145664817600 |
13 | 3196100636757760 |
14 | 66834662101834240 |
15 | 1407913577733228544 |
16 | 29849617614785770456 |
17 | 636440695668355742560 |
18 | 13638210075999240396736 |
19 | 293565508750164008207104 |
20 | 6344596821114216520841536 |
[1,4,40,544,8536,145504,2618176,48943360, 941244376,18502137184,370091343040,7508629231360, 154145664817600,3196100636757760, 66834662101834240,1407913577733228544, 29849617614785770456,636440695668355742560, 13638210075999240396736,293565508750164008207104, 6344596821114216520841536] |