n | a(n) |
---|---|
0 | 1 |
1 | 1 |
2 | 3 |
3 | 13 |
4 | 71 |
5 | 441 |
6 | 2955 |
7 | 20805 |
8 | 151695 |
9 | 1135345 |
10 | 8671763 |
11 | 67320573 |
12 | 529626839 |
13 | 4213228969 |
14 | 33833367963 |
15 | 273892683573 |
16 | 2232832964895 |
17 | 18314495896545 |
18 | 151037687326755 |
19 | 1251606057754605 |
20 | 10416531069771111 |
21 | 87029307323766681 |
[1,1,3,13,71,441,2955,20805,151695,1135345, 8671763,67320573,529626839,4213228969,33833367963, 273892683573,2232832964895,18314495896545, 151037687326755,1251606057754605, 10416531069771111,87029307323766681] |