n | a(n) |
---|---|
3 | 1 |
4 | 2 |
5 | 5 |
6 | 17 |
7 | 68 |
8 | 267 |
9 | 1230 |
10 | 5564 |
11 | 27575 |
12 | 136644 |
13 | 714772 |
14 | 3743265 |
15 | 20353789 |
16 | 110723361 |
17 | 619347223 |
18 | 3464770044 |
19 | 19801412122 |
20 | 113178582936 |
[1,2,5,17,68,267,1230,5564,27575,136644,714772, 3743265,20353789,110723361,619347223,3464770044, 19801412122,113178582936] |