n | a(n) |
---|---|
0 | 0 |
1 | 2 |
2 | 6 |
3 | 34 |
4 | 220 |
5 | 1868 |
6 | 18648 |
7 | 222696 |
8 | 3061728 |
9 | 48199392 |
10 | 852857280 |
11 | 16813212480 |
12 | 365177928960 |
13 | 8671294183680 |
14 | 223409173317120 |
15 | 6207795845798400 |
16 | 185021865565286400 |
17 | 5887763630809804800 |
18 | 199220359130518118400 |
19 | 7141874528908565913600 |
20 | 270391380094261923840000 |
[0,2,6,34,220,1868,18648,222696,3061728,48199392, 852857280,16813212480,365177928960,8671294183680, 223409173317120,6207795845798400, 185021865565286400,5887763630809804800, 199220359130518118400,7141874528908565913600, 270391380094261923840000] |