n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 2 |
4 | 6 |
5 | 16 |
6 | 45 |
7 | 128 |
8 | 448 |
9 | 1706 |
10 | 6528 |
11 | 24576 |
12 | 90110 |
13 | 327680 |
14 | 1198665 |
15 | 4438966 |
16 | 16646144 |
17 | 62914560 |
18 | 238605640 |
19 | 905969664 |
20 | 3442684722 |
21 | 13102206738 |
22 | 49977848925 |
23 | 191126044672 |
24 | 732649837760 |
25 | 2814062572336 |
26 | 10825959997440 |
27 | 41705086880768 |
28 | 160862477970870 |
[0,0,2,6,16,45,128,448,1706,6528,24576,90110, 327680,1198665,4438966,16646144,62914560, 238605640,905969664,3442684722,13102206738, 49977848925,191126044672,732649837760, 2814062572336,10825959997440,41705086880768, 160862477970870] |