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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 9 |
| 3 | 16 |
| 4 | 50 |
| 5 | 138 |
| 6 | 387 |
| 7 | 1143 |
| 8 | 3402 |
| 9 | 9948 |
| 10 | 30747 |
| 11 | 90018 |
| 12 | 266959 |
| 13 | 805676 |
| 14 | 2433677 |
| 15 | 7192342 |
| 16 | 21660095 |
| 17 | 64921118 |
| 18 | 194318785 |
| 19 | 583516248 |
| 20 | 1749692999 |
| 21 | 5235795129 |
| 22 | 15779920510 |
| 23 | 47191559739 |
| 24 | 141322913448 |
| 25 | 424521847845 |
| 26 | 1275708336588 |
[3,9,16,50,138,387,1143,3402,9948,30747,90018, 266959,805676,2433677,7192342,21660095,64921118, 194318785,583516248,1749692999,5235795129, 15779920510,47191559739,141322913448,424521847845, 1275708336588] |