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| n | a(n) |
|---|---|
| 1 | 12 |
| 2 | 13 |
| 3 | 21 |
| 4 | 31 |
| 5 | 33 |
| 6 | 99 |
| 7 | 102 |
| 8 | 103 |
| 9 | 112 |
| 10 | 113 |
| 11 | 122 |
| 12 | 201 |
| 13 | 211 |
| 14 | 221 |
| 15 | 301 |
| 16 | 311 |
| 17 | 1002 |
| 18 | 1003 |
| 19 | 1011 |
| 20 | 1012 |
| 21 | 1013 |
| 22 | 1021 |
| 23 | 1022 |
| 24 | 1031 |
| 25 | 1101 |
| 26 | 1102 |
| 27 | 1103 |
| 28 | 1112 |
| 29 | 1113 |
| 30 | 1121 |
| 31 | 1122 |
| 32 | 1201 |
| 33 | 1202 |
| 34 | 1211 |
| 35 | 1212 |
| 36 | 1301 |
| 37 | 2001 |
| 38 | 2011 |
| 39 | 2012 |
| 40 | 2021 |
| 41 | 2022 |
| 42 | 2101 |
| 43 | 2102 |
| 44 | 2111 |
| 45 | 2121 |
[12,13,21,31,33,99,102,103,112,113,122,201,211, 221,301,311,1002,1003,1011,1012,1013,1021,1022, 1031,1101,1102,1103,1112,1113,1121,1122,1201,1202, 1211,1212,1301,2001,2011,2012,2021,2022,2101,2102, 2111,2121] |