n | a(n) |
---|---|
0 | 1 |
1 | 5 |
2 | 20 |
3 | 72 |
4 | 280 |
5 | 1080 |
6 | 4216 |
7 | 16632 |
8 | 66040 |
9 | 263160 |
10 | 1050616 |
11 | 4198392 |
12 | 16785400 |
13 | 67125240 |
14 | 268468216 |
15 | 1073807352 |
[1,5,20,72,280,1080,4216,16632,66040,263160, 1050616,4198392,16785400,67125240,268468216, 1073807352] |