n | a(n) |
---|---|
0 | 1 |
1 | 2 |
2 | 6 |
3 | 30 |
4 | 192 |
5 | 1480 |
6 | 13500 |
7 | 141540 |
8 | 1676640 |
9 | 22141728 |
10 | 322388640 |
11 | 5130084960 |
12 | 88561408320 |
13 | 1648294876800 |
14 | 32898981155040 |
15 | 700940855815200 |
16 | 15877318955097600 |
17 | 380996919471168000 |
18 | 9654670629548904960 |
19 | 257627854786123261440 |
20 | 7220676423560766566400 |
[1,2,6,30,192,1480,13500,141540,1676640,22141728, 322388640,5130084960,88561408320,1648294876800, 32898981155040,700940855815200,15877318955097600, 380996919471168000,9654670629548904960, 257627854786123261440,7220676423560766566400] |