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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 11 |
| 4 | 13 |
| 5 | 31 |
| 6 | 111 |
| 7 | 113 |
| 8 | 131 |
| 9 | 133 |
| 10 | 311 |
| 11 | 1113 |
| 12 | 1131 |
| 13 | 1133 |
| 14 | 1311 |
| 15 | 1331 |
| 16 | 3111 |
| 17 | 3113 |
| 18 | 11131 |
| 19 | 11133 |
| 20 | 11311 |
| 21 | 11331 |
| 22 | 13111 |
| 23 | 13113 |
| 24 | 13311 |
| 25 | 31131 |
| 26 | 31133 |
| 27 | 111311 |
| 28 | 111331 |
| 29 | 113111 |
| 30 | 113311 |
| 31 | 311311 |
| 32 | 311331 |
| 33 | 1113111 |
| 34 | 1113311 |
| 35 | 3113111 |
| 36 | 3113311 |
[1,3,11,13,31,111,113,131,133,311,1113,1131,1133, 1311,1331,3111,3113,11131,11133,11311,11331,13111, 13113,13311,31131,31133,111311,111331,113111, 113311,311311,311331,1113111,1113311,3113111, 3113311] |