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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 8 |
| 4 | 28 |
| 5 | 107 |
| 6 | 405 |
| 7 | 1520 |
| 8 | 5706 |
| 9 | 21418 |
| 10 | 80390 |
| 11 | 301736 |
| 12 | 1132543 |
| 13 | 4250895 |
| 14 | 15955408 |
| 15 | 59887275 |
| 16 | 224782132 |
| 17 | 843701335 |
| 18 | 3166765105 |
| 19 | 11886195940 |
| 20 | 44613876758 |
| 21 | 167454575870 |
| 22 | 628527215306 |
| 23 | 2359126067724 |
| 24 | 8854788952291 |
| 25 | 33235734276043 |
[1,1,8,28,107,405,1520,5706,21418,80390,301736, 1132543,4250895,15955408,59887275,224782132, 843701335,3166765105,11886195940,44613876758, 167454575870,628527215306,2359126067724, 8854788952291,33235734276043] |