n | a(n) |
---|---|
0 | 0 |
1 | 0 |
2 | 0 |
3 | 1 |
4 | 7 |
5 | 35 |
6 | 154 |
7 | 637 |
8 | 2548 |
9 | 9996 |
10 | 38760 |
11 | 149226 |
12 | 572033 |
13 | 2187185 |
14 | 8351070 |
15 | 31865925 |
16 | 121580760 |
17 | 463991880 |
18 | 1771605360 |
19 | 6768687870 |
20 | 25880277150 |
21 | 99035193894 |
22 | 379300783092 |
23 | 1453986335186 |
24 | 5578559816632 |
25 | 21422369201800 |
26 | 82336410323440 |
27 | 316729578421620 |
[0,0,0,1,7,35,154,637,2548,9996,38760,149226, 572033,2187185,8351070,31865925,121580760, 463991880,1771605360,6768687870,25880277150, 99035193894,379300783092,1453986335186, 5578559816632,21422369201800,82336410323440, 316729578421620] |