n | a(n) |
---|---|
1 | 1 |
2 | 0 |
3 | 0 |
4 | 2 |
5 | 0 |
6 | 0 |
7 | 0 |
8 | 0 |
9 | 0 |
10 | 4 |
11 | 56 |
12 | 172 |
13 | 680 |
14 | 1348 |
15 | 6576 |
16 | 34568 |
17 | 107624 |
18 | 413760 |
19 | 1697288 |
20 | 8035558 |
21 | 37441416 |
22 | 192483420 |
23 | 1115143224 |
[1,0,0,2,0,0,0,0,0,4,56,172,680,1348,6576,34568, 107624,413760,1697288,8035558,37441416,192483420, 1115143224] |