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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 38 |
| 5 | 134 |
| 6 | 584 |
| 7 | 2309 |
| 8 | 10312 |
| 9 | 43552 |
| 10 | 198091 |
| 11 | 867511 |
| 12 | 4004962 |
| 13 | 17954426 |
| 14 | 83845509 |
| 15 | 382281459 |
| 16 | 1800809791 |
| 17 | 8315906216 |
| 18 | 39437787069 |
| 19 | 183934361353 |
| 20 | 876998515467 |
| 21 | 4122741474682 |
| 22 | 19744173018101 |
| 23 | 93415657609540 |
| 24 | 449030482387146 |
| 25 | 2135822467364331 |
| 26 | 10298633928282830 |
| 27 | 49204742449051467 |
[1,1,3,9,38,134,584,2309,10312,43552,198091, 867511,4004962,17954426,83845509,382281459, 1800809791,8315906216,39437787069,183934361353, 876998515467,4122741474682,19744173018101, 93415657609540,449030482387146,2135822467364331, 10298633928282830,49204742449051467] |