n | a(n) |
---|---|
0 | 0 |
1 | 6 |
2 | 84 |
3 | 780 |
4 | 5880 |
5 | 39060 |
6 | 238392 |
7 | 1369368 |
8 | 7516080 |
9 | 39819780 |
10 | 205079160 |
11 | 1032047016 |
12 | 5094629904 |
13 | 24743027400 |
14 | 118504436400 |
15 | 560749834800 |
16 | 2625519143520 |
17 | 12179090862180 |
18 | 56029885342200 |
19 | 255864364648200 |
[0,6,84,780,5880,39060,238392,1369368,7516080, 39819780,205079160,1032047016,5094629904, 24743027400,118504436400,560749834800, 2625519143520,12179090862180,56029885342200, 255864364648200] |