n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 1 |
3 | 2 |
4 | 3 |
5 | 12 |
6 | 40 |
7 | 120 |
8 | 2520 |
9 | 5040 |
10 | 10080 |
11 | 5040 |
12 | 19958400 |
13 | 19958400 |
14 | 259459200 |
15 | 518918400 |
16 | 2179457280 |
17 | 4358914560 |
18 | 1235025792000 |
19 | 3705077376000 |
20 | 422378820864000 |
21 | 52797352608000 |
22 | 120679663104000 |
23 | 844757641728000 |
[1,1,1,2,3,12,40,120,2520,5040,10080,5040, 19958400,19958400,259459200,518918400,2179457280, 4358914560,1235025792000,3705077376000, 422378820864000,52797352608000,120679663104000, 844757641728000] |