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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 28 |
| 5 | 91 |
| 6 | 307 |
| 7 | 1067 |
| 8 | 3792 |
| 9 | 13702 |
| 10 | 50148 |
| 11 | 185416 |
| 12 | 691277 |
| 13 | 2595167 |
| 14 | 9800041 |
| 15 | 37194707 |
| 16 | 141787644 |
| 17 | 542583488 |
| 18 | 2083404030 |
| 19 | 8024142706 |
| 20 | 30988922366 |
| 21 | 119972435149 |
| 22 | 465505007827 |
| 23 | 1809877343351 |
| 24 | 7049866113619 |
| 25 | 27507668129630 |
[1,3,9,28,91,307,1067,3792,13702,50148,185416, 691277,2595167,9800041,37194707,141787644, 542583488,2083404030,8024142706,30988922366, 119972435149,465505007827,1809877343351, 7049866113619,27507668129630] |