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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 13 |
| 4 | 31 |
| 5 | 79 |
| 6 | 168 |
| 7 | 430 |
| 8 | 1241 |
| 9 | 3577 |
| 10 | 10976 |
| 11 | 35220 |
| 12 | 115104 |
| 13 | 382846 |
| 14 | 1287463 |
| 15 | 4355297 |
| 16 | 14794917 |
| 17 | 50378019 |
| 18 | 171779607 |
| 19 | 586281739 |
| 20 | 2002004862 |
| 21 | 6838403076 |
| 22 | 23363178277 |
| 23 | 79828543393 |
| 24 | 272780054792 |
| 25 | 932149927652 |
| 26 | 3185441895514 |
[3,9,13,31,79,168,430,1241,3577,10976,35220, 115104,382846,1287463,4355297,14794917,50378019, 171779607,586281739,2002004862,6838403076, 23363178277,79828543393,272780054792,932149927652, 3185441895514] |