| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 15 |
| 5 | 39 |
| 6 | 135 |
| 7 | 382 |
| 8 | 1543 |
| 9 | 4843 |
| 10 | 18881 |
| 11 | 60918 |
| 12 | 256074 |
| 13 | 874174 |
| 14 | 3590229 |
| 15 | 12412052 |
| 16 | 53420218 |
| 17 | 191510935 |
| 18 | 810050590 |
| 19 | 2923309230 |
| 20 | 12779202552 |
| 21 | 47321530017 |
| 22 | 204011303079 |
| 23 | 758221407024 |
| 24 | 3351513850093 |
| 25 | 12701475190962 |
| 26 | 55496678400253 |
| 27 | 210743047646368 |
| 28 | 939312182558310 |
| 29 | 3622442515633786 |
[1,1,2,4,15,39,135,382,1543,4843,18881,60918, 256074,874174,3590229,12412052,53420218,191510935, 810050590,2923309230,12779202552,47321530017, 204011303079,758221407024,3351513850093, 12701475190962,55496678400253,210743047646368, 939312182558310,3622442515633786] |