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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 9 |
| 3 | 4 |
| 4 | 23 |
| 5 | 38 |
| 6 | 22 |
| 7 | 36 |
| 8 | 140 |
| 9 | 146 |
| 10 | 218 |
| 11 | 736 |
| 12 | 1072 |
| 13 | 1890 |
| 14 | 4505 |
| 15 | 8860 |
| 16 | 16665 |
| 17 | 36236 |
| 18 | 77955 |
| 19 | 157132 |
| 20 | 339776 |
| 21 | 741215 |
| 22 | 1574853 |
| 23 | 3425156 |
| 24 | 7498971 |
| 25 | 16329476 |
| 26 | 35728895 |
| 27 | 78504972 |
| 28 | 172477510 |
| 29 | 378971254 |
| 30 | 834963467 |
| 31 | 1839342289 |
| 32 | 4053198576 |
| 33 | 8939535791 |
[0,9,4,23,38,22,36,140,146,218,736,1072,1890,4505, 8860,16665,36236,77955,157132,339776,741215, 1574853,3425156,7498971,16329476,35728895, 78504972,172477510,378971254,834963467,1839342289, 4053198576,8939535791] |