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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 26 |
| 5 | 92 |
| 6 | 311 |
| 7 | 1161 |
| 8 | 4418 |
| 9 | 16770 |
| 10 | 66734 |
| 11 | 264292 |
| 12 | 1066008 |
| 13 | 4380303 |
| 14 | 17942834 |
| 15 | 74820454 |
| 16 | 313808725 |
| 17 | 1319581995 |
| 18 | 5616581050 |
| 19 | 23932844268 |
| 20 | 102589135624 |
| 21 | 442708044443 |
| 22 | 1912059874482 |
| 23 | 8310231577525 |
| 24 | 36231490886389 |
| 25 | 158281403031522 |
| 26 | 694917637204853 |
| 27 | 3055506420550141 |
| 28 | 13473895432254104 |
[1,1,3,8,26,92,311,1161,4418,16770,66734,264292, 1066008,4380303,17942834,74820454,313808725, 1319581995,5616581050,23932844268,102589135624, 442708044443,1912059874482,8310231577525, 36231490886389,158281403031522,694917637204853, 3055506420550141,13473895432254104] |