n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 1 |
3 | 3 |
4 | 6 |
5 | 20 |
6 | 67 |
7 | 291 |
8 | 1099 |
9 | 5780 |
10 | 26249 |
11 | 153238 |
12 | 832366 |
13 | 5443440 |
14 | 32738738 |
15 | 239515824 |
16 | 1591963864 |
17 | 12548347149 |
18 | 93066370414 |
[1,1,1,3,6,20,67,291,1099,5780,26249,153238, 832366,5443440,32738738,239515824,1591963864, 12548347149,93066370414] |