n | a(n) |
---|---|
0 | 1 |
1 | 2 |
2 | 18 |
3 | 180 |
4 | 1890 |
5 | 20412 |
6 | 224532 |
7 | 2501928 |
8 | 28146690 |
9 | 318995820 |
10 | 3636552348 |
11 | 41655054168 |
12 | 479033122932 |
13 | 5527305264600 |
14 | 63958818061800 |
15 | 741922289516880 |
16 | 8624846615633730 |
17 | 100454095876204620 |
18 | 1171964451889053900 |
19 | 13693479385229998200 |
20 | 160213708807190978940 |
[1,2,18,180,1890,20412,224532,2501928,28146690, 318995820,3636552348,41655054168,479033122932, 5527305264600,63958818061800,741922289516880, 8624846615633730,100454095876204620, 1171964451889053900,13693479385229998200, 160213708807190978940] |