n | a(n) |
---|---|
0 | 1 |
1 | 4 |
2 | 22 |
3 | 152 |
4 | 1241 |
5 | 11444 |
6 | 115390 |
7 | 1243672 |
8 | 14104480 |
9 | 166460800 |
10 | 2028202288 |
11 | 25363355200 |
12 | 324098616925 |
13 | 4217387014948 |
14 | 55737166570870 |
15 | 746544123583928 |
16 | 10116388473816503 |
17 | 138496854665195996 |
18 | 1913322982776458234 |
19 | 26646647187379206440 |
20 | 373800949052597088329 |
[1,4,22,152,1241,11444,115390,1243672,14104480, 166460800,2028202288,25363355200,324098616925, 4217387014948,55737166570870,746544123583928, 10116388473816503,138496854665195996, 1913322982776458234,26646647187379206440, 373800949052597088329] |