n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 0 |
3 | 2 |
4 | 6 |
5 | 24 |
6 | 160 |
7 | 1140 |
8 | 8988 |
9 | 80864 |
10 | 809856 |
11 | 8907480 |
12 | 106877320 |
13 | 1389428832 |
14 | 19452141696 |
15 | 291781655984 |
16 | 4668504894480 |
17 | 79364592318720 |
18 | 1428562679845888 |
19 | 27142690734936864 |
20 | 542853814536802656 |
21 | 11399930109077490560 |
22 | 250798462399300784640 |
[1,0,0,2,6,24,160,1140,8988,80864,809856,8907480, 106877320,1389428832,19452141696,291781655984, 4668504894480,79364592318720,1428562679845888, 27142690734936864,542853814536802656, 11399930109077490560,250798462399300784640] |