n | a(n) |
---|---|
1 | 1 |
2 | 1 |
3 | 1 |
4 | 1 |
5 | 1 |
6 | 5 |
7 | 17 |
8 | 39 |
9 | 137 |
10 | 661 |
11 | 3965 |
12 | 30475 |
13 | 261877 |
14 | 2593597 |
15 | 32463645 |
16 | 507974205 |
17 | 9631596681 |
18 | 224195557727 |
19 | 6341197277447 |
20 | 216685113312141 |
21 | 8987183183859385 |
[1,1,1,1,1,5,17,39,137,661,3965,30475,261877, 2593597,32463645,507974205,9631596681, 224195557727,6341197277447,216685113312141, 8987183183859385] |