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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 9 |
| 4 | 28 |
| 5 | 95 |
| 6 | 306 |
| 7 | 987 |
| 8 | 3144 |
| 9 | 9963 |
| 10 | 31390 |
| 11 | 98483 |
| 12 | 307836 |
| 13 | 959257 |
| 14 | 2981174 |
| 15 | 9243405 |
| 16 | 28601712 |
| 17 | 88342659 |
| 18 | 272428758 |
| 19 | 838903371 |
| 20 | 2579937060 |
| 21 | 7924966749 |
| 22 | 24317716038 |
| 23 | 74546117121 |
| 24 | 228317474952 |
| 25 | 698708409525 |
| 26 | 2136597743826 |
[1,2,9,28,95,306,987,3144,9963,31390,98483,307836, 959257,2981174,9243405,28601712,88342659, 272428758,838903371,2579937060,7924966749, 24317716038,74546117121,228317474952,698708409525, 2136597743826] |