n | a(n) |
---|---|
1 | 0 |
2 | 1 |
3 | 0 |
4 | 1 |
5 | 1 |
6 | 3 |
7 | 6 |
8 | 14 |
9 | 42 |
10 | 121 |
11 | 384 |
12 | 1408 |
13 | 5100 |
14 | 21854 |
15 | 92234 |
16 | 427079 |
17 | 2005800 |
18 | 9716848 |
19 | 48184018 |
20 | 241210386 |
21 | 1228973463 |
22 | 6301831944 |
23 | 32663182521 |
24 | 170407462900 |
[0,1,0,1,1,3,6,14,42,121,384,1408,5100,21854, 92234,427079,2005800,9716848,48184018,241210386, 1228973463,6301831944,32663182521,170407462900] |