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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 3 |
| 3 | 6 |
| 4 | 7 |
| 5 | 16 |
| 6 | 19 |
| 7 | 46 |
| 8 | 66 |
| 9 | 159 |
| 10 | 274 |
| 11 | 667 |
| 12 | 1320 |
| 13 | 3263 |
| 14 | 7156 |
| 15 | 18084 |
| 16 | 42794 |
| 17 | 111018 |
| 18 | 278752 |
| 19 | 743889 |
| 20 | 1959482 |
| 21 | 5383395 |
| 22 | 14761634 |
| 23 | 41740307 |
| 24 | 118517301 |
| 25 | 344580865 |
| 26 | 1009349749 |
| 27 | 3013665637 |
| 28 | 9081346743 |
| 29 | 27808754039 |
| 30 | 86015003997 |
| 31 | 269796018547 |
[1,2,3,6,7,16,19,46,66,159,274,667,1320,3263,7156, 18084,42794,111018,278752,743889,1959482,5383395, 14761634,41740307,118517301,344580865,1009349749, 3013665637,9081346743,27808754039,86015003997, 269796018547] |