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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 37 |
| 5 | 184 |
| 6 | 959 |
| 7 | 5172 |
| 8 | 28641 |
| 9 | 162008 |
| 10 | 932503 |
| 11 | 5445934 |
| 12 | 32197334 |
| 13 | 192357788 |
| 14 | 1159603592 |
| 15 | 7045356104 |
| 16 | 43098733353 |
| 17 | 265240985112 |
| 18 | 1641100253735 |
| 19 | 10202295895890 |
| 20 | 63696629668980 |
| 21 | 399216722146770 |
| 22 | 2510833297584165 |
[1,2,8,37,184,959,5172,28641,162008,932503, 5445934,32197334,192357788,1159603592,7045356104, 43098733353,265240985112,1641100253735, 10202295895890,63696629668980,399216722146770, 2510833297584165] |