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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 11 |
| 4 | 15 |
| 5 | 27 |
| 6 | 77 |
| 7 | 227 |
| 8 | 527 |
| 9 | 715 |
| 10 | 1515 |
| 11 | 1711 |
| 12 | 2777 |
| 13 | 7227 |
| 14 | 7715 |
| 15 | 22715 |
| 16 | 52915 |
| 17 | 71911 |
| 18 | 97527 |
| 19 | 159911 |
| 20 | 275527 |
| 21 | 277977 |
| 22 | 715511 |
| 23 | 727511 |
| 24 | 977511 |
| 25 | 2791515 |
| 26 | 7219777 |
| 27 | 7557511 |
| 28 | 7715515 |
| 29 | 7727711 |
| 30 | 7727715 |
| 31 | 9591515 |
| 32 | 9777515 |
| 33 | 9797511 |
| 34 | 9797715 |
| 35 | 9955511 |
| 36 | 11292915 |
| 37 | 12292915 |
| 38 | 17255515 |
| 39 | 27771527 |
| 40 | 27797715 |
| 41 | 27797977 |
| 42 | 27915515 |
| 43 | 71971911 |
| 44 | 72299211 |
[1,5,11,15,27,77,227,527,715,1515,1711,2777,7227, 7715,22715,52915,71911,97527,159911,275527,277977, 715511,727511,977511,2791515,7219777,7557511, 7715515,7727711,7727715,9591515,9777515,9797511, 9797715,9955511,11292915,12292915,17255515, 27771527,27797715,27797977,27915515,71971911, 72299211] |