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| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 9 |
| 2 | 33 |
| 3 | 111 |
| 4 | 387 |
| 5 | 1329 |
| 6 | 4593 |
| 7 | 15831 |
| 8 | 54627 |
| 9 | 188409 |
| 10 | 649953 |
| 11 | 2241951 |
| 12 | 7733667 |
| 13 | 26677089 |
| 14 | 92022513 |
| 15 | 317430471 |
| 16 | 1094973507 |
| 17 | 3777099369 |
| 18 | 13029066273 |
| 19 | 44943629391 |
| 20 | 155032590147 |
| 21 | 534783327249 |
| 22 | 1844729605233 |
| 23 | 6363375846711 |
[3,9,33,111,387,1329,4593,15831,54627,188409, 649953,2241951,7733667,26677089,92022513, 317430471,1094973507,3777099369,13029066273, 44943629391,155032590147,534783327249, 1844729605233,6363375846711] |