n | a(n) |
---|---|
1 | 0 |
2 | 0 |
3 | 1 |
4 | 7 |
5 | 36 |
6 | 168 |
7 | 736 |
8 | 3151 |
9 | 13190 |
10 | 54938 |
11 | 226597 |
12 | 934200 |
13 | 3831219 |
14 | 15723801 |
15 | 64313623 |
16 | 263316219 |
17 | 1075420890 |
18 | 4396310382 |
19 | 17937457304 |
20 | 73247306563 |
21 | 298635873550 |
22 | 1218428664338 |
[0,0,1,7,36,168,736,3151,13190,54938,226597, 934200,3831219,15723801,64313623,263316219, 1075420890,4396310382,17937457304,73247306563, 298635873550,1218428664338] |