n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 1 |
3 | 6 |
4 | 40 |
5 | 320 |
6 | 2946 |
7 | 29364 |
8 | 309558 |
9 | 3365108 |
10 | 37246245 |
11 | 416751008 |
12 | 4696232371 |
13 | 53186743416 |
14 | 604690121555 |
15 | 6896534910612 |
16 | 78867385697513 |
17 | 904046279771682 |
18 | 10384916465797240 |
19 | 119522063788612992 |
20 | 1378014272286250059 |
[0,0,1,6,40,320,2946,29364,309558,3365108, 37246245,416751008,4696232371,53186743416, 604690121555,6896534910612,78867385697513, 904046279771682,10384916465797240, 119522063788612992,1378014272286250059] |