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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 3 |
| 3 | 9 |
| 4 | 9 |
| 5 | 50 |
| 6 | 50 |
| 7 | 204 |
| 8 | 204 |
| 9 | 1135 |
| 10 | 1135 |
| 11 | 6086 |
| 12 | 6086 |
| 13 | 36018 |
| 14 | 36018 |
| 15 | 216932 |
| 16 | 216932 |
| 17 | 1306070 |
| 18 | 1306070 |
| 19 | 8129138 |
| 20 | 8129138 |
| 21 | 51773946 |
| 22 | 51773946 |
| 23 | 326701423 |
| 24 | 326701423 |
[3,3,9,9,50,50,204,204,1135,1135,6086,6086,36018, 36018,216932,216932,1306070,1306070,8129138, 8129138,51773946,51773946,326701423,326701423] |