| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 12 |
| 5 | 34 |
| 6 | 111 |
| 7 | 360 |
| 8 | 1226 |
| 9 | 4206 |
| 10 | 14728 |
| 11 | 52024 |
| 12 | 185824 |
| 13 | 668676 |
| 14 | 2424033 |
| 15 | 8839632 |
| 16 | 32412270 |
| 17 | 119410390 |
| 18 | 441819444 |
| 19 | 1641032536 |
| 20 | 6116579352 |
| 21 | 22870649308 |
| 22 | 85764947502 |
| 23 | 322476066224 |
| 24 | 1215486756372 |
| 25 | 4591838372044 |
[1,2,4,12,34,111,360,1226,4206,14728,52024,185824, 668676,2424033,8839632,32412270,119410390, 441819444,1641032536,6116579352,22870649308, 85764947502,322476066224,1215486756372, 4591838372044] |