n | a(n) |
---|---|
1 | 0 |
2 | 6 |
3 | 20 |
4 | 180 |
5 | 644 |
6 | 5502 |
7 | 20292 |
8 | 174456 |
9 | 654632 |
10 | 5673140 |
11 | 21528000 |
12 | 187675644 |
13 | 717800628 |
14 | 6284986554 |
15 | 24178479500 |
16 | 212408191568 |
17 | 820811282352 |
18 | 7229648901024 |
19 | 28037230854096 |
20 | 247468885359240 |
21 | 962488105227160 |
22 | 8510025522045036 |
23 | 33177800527098040 |
24 | 293772371437293720 |
[0,6,20,180,644,5502,20292,174456,654632,5673140, 21528000,187675644,717800628,6284986554, 24178479500,212408191568,820811282352, 7229648901024,28037230854096,247468885359240, 962488105227160,8510025522045036, 33177800527098040,293772371437293720] |