n | a(n) |
---|---|
0 | 1 |
1 | 0 |
2 | 1 |
3 | 1 |
4 | 7 |
5 | 21 |
6 | 126 |
7 | 638 |
8 | 4264 |
9 | 28983 |
10 | 226018 |
11 | 1872300 |
12 | 16940661 |
13 | 163461455 |
14 | 1688378030 |
15 | 18501971647 |
16 | 214749109038 |
17 | 2628228896227 |
18 | 33832314246857 |
19 | 456730760934125 |
20 | 6451399211318995 |
21 | 95135434800384144 |
22 | 1461771954435844296 |
23 | 23360315241127222572 |
[1,0,1,1,7,21,126,638,4264,28983,226018,1872300, 16940661,163461455,1688378030,18501971647, 214749109038,2628228896227,33832314246857, 456730760934125,6451399211318995, 95135434800384144,1461771954435844296, 23360315241127222572] |