| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 14 |
| 4 | 75 |
| 5 | 438 |
| 6 | 2704 |
| 7 | 17356 |
| 8 | 114661 |
| 9 | 774514 |
| 10 | 5324812 |
| 11 | 37137379 |
| 12 | 262112002 |
| 13 | 1868610856 |
| 14 | 13436074970 |
| 15 | 97328988039 |
| 16 | 709609323325 |
| 17 | 5203171782012 |
| 18 | 38345109874752 |
| 19 | 283864224950635 |
| 20 | 2109947626538162 |
| 21 | 15740670860816827 |
| 22 | 117819995601231131 |
| 23 | 884569446129847355 |
[1,1,3,14,75,438,2704,17356,114661,774514,5324812, 37137379,262112002,1868610856,13436074970, 97328988039,709609323325,5203171782012, 38345109874752,283864224950635,2109947626538162, 15740670860816827,117819995601231131, 884569446129847355] |