n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 2 |
4 | 12 |
5 | 70 |
6 | 442 |
7 | 3108 |
8 | 24216 |
9 | 208586 |
10 | 1972904 |
11 | 20373338 |
12 | 228346522 |
13 | 2763212980 |
14 | 35926266244 |
15 | 499676669254 |
16 | 7405014187564 |
17 | 116511984902094 |
18 | 1940073930857802 |
19 | 34087525861589564 |
20 | 630296344519286304 |
21 | 12235215845125112122 |
22 | 248789737587365945992 |
[0,0,2,12,70,442,3108,24216,208586,1972904, 20373338,228346522,2763212980,35926266244, 499676669254,7405014187564,116511984902094, 1940073930857802,34087525861589564, 630296344519286304,12235215845125112122, 248789737587365945992] |