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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 13 |
| 4 | 31 |
| 5 | 113 |
| 6 | 131 |
| 7 | 133 |
| 8 | 311 |
| 9 | 313 |
| 10 | 331 |
| 11 | 1113 |
| 12 | 1131 |
| 13 | 1133 |
| 14 | 1311 |
| 15 | 1331 |
| 16 | 1333 |
| 17 | 3111 |
| 18 | 3113 |
| 19 | 3133 |
| 20 | 3311 |
| 21 | 3313 |
| 22 | 3331 |
| 23 | 11113 |
| 24 | 11131 |
| 25 | 11133 |
| 26 | 11311 |
| 27 | 11313 |
| 28 | 11331 |
| 29 | 11333 |
| 30 | 13111 |
| 31 | 13113 |
| 32 | 13131 |
| 33 | 13133 |
| 34 | 13311 |
| 35 | 13313 |
| 36 | 13331 |
| 37 | 13333 |
| 38 | 31111 |
| 39 | 31113 |
| 40 | 31131 |
| 41 | 31133 |
| 42 | 31311 |
| 43 | 31313 |
| 44 | 31331 |
| 45 | 31333 |
| 46 | 33111 |
| 47 | 33113 |
| 48 | 33131 |
| 49 | 33133 |
| 50 | 33311 |
| 51 | 33313 |
| 52 | 33331 |
[1,3,13,31,113,131,133,311,313,331,1113,1131,1133, 1311,1331,1333,3111,3113,3133,3311,3313,3331, 11113,11131,11133,11311,11313,11331,11333,13111, 13113,13131,13133,13311,13313,13331,13333,31111, 31113,31131,31133,31311,31313,31331,31333,33111, 33113,33131,33133,33311,33313,33331] |