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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 6 |
| 3 | 13 |
| 4 | 27 |
| 5 | 51 |
| 6 | 91 |
| 7 | 159 |
| 8 | 273 |
| 9 | 455 |
| 10 | 738 |
| 11 | 1179 |
| 12 | 1860 |
| 13 | 2886 |
| 14 | 4410 |
| 15 | 6667 |
| 16 | 9981 |
| 17 | 14781 |
| 18 | 21671 |
| 19 | 31512 |
| 20 | 45474 |
| 21 | 65113 |
| 22 | 92547 |
| 23 | 130689 |
| 24 | 183439 |
| 25 | 255930 |
| 26 | 355017 |
| 27 | 489895 |
| 28 | 672672 |
| 29 | 919152 |
| 30 | 1250107 |
| 31 | 1692846 |
| 32 | 2282895 |
| 33 | 3066180 |
| 34 | 4102224 |
| 35 | 5468160 |
| 36 | 7263217 |
| 37 | 9614436 |
| 38 | 12684633 |
| 39 | 16682276 |
[1,3,6,13,27,51,91,159,273,455,738,1179,1860,2886, 4410,6667,9981,14781,21671,31512,45474,65113, 92547,130689,183439,255930,355017,489895,672672, 919152,1250107,1692846,2282895,3066180,4102224, 5468160,7263217,9614436,12684633,16682276] |