| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 11 |
| 5 | 44 |
| 6 | 185 |
| 7 | 803 |
| 8 | 3564 |
| 9 | 16082 |
| 10 | 73502 |
| 11 | 339391 |
| 12 | 1580318 |
| 13 | 7410356 |
| 14 | 34956846 |
| 15 | 165756814 |
| 16 | 789543189 |
| 17 | 3775883483 |
| 18 | 18122280953 |
| 19 | 87257629998 |
| 20 | 421366007784 |
| 21 | 2040186607333 |
| 22 | 9902368905093 |
| 23 | 48170863713973 |
| 24 | 234819266573684 |
| 25 | 1146894750998644 |
| 26 | 5611743950271715 |
| 27 | 27504683191546135 |
[1,1,3,11,44,185,803,3564,16082,73502,339391, 1580318,7410356,34956846,165756814,789543189, 3775883483,18122280953,87257629998,421366007784, 2040186607333,9902368905093,48170863713973, 234819266573684,1146894750998644,5611743950271715, 27504683191546135] |