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| n | a(n) |
|---|---|
| 0 | 1001 |
| 1 | 1111 |
| 2 | 1221 |
| 3 | 1331 |
| 4 | 1441 |
| 5 | 1551 |
| 6 | 1661 |
| 7 | 1771 |
| 8 | 1881 |
| 9 | 1991 |
| 10 | 110101 |
| 11 | 111111 |
| 12 | 112121 |
| 13 | 113131 |
| 14 | 114141 |
| 15 | 115151 |
| 16 | 116161 |
| 17 | 117171 |
| 18 | 118181 |
| 19 | 119191 |
| 20 | 120201 |
| 21 | 121211 |
| 22 | 122221 |
| 23 | 123231 |
| 24 | 124241 |
| 25 | 125251 |
| 26 | 126261 |
| 27 | 127271 |
| 28 | 128281 |
| 29 | 129291 |
| 30 | 130301 |
| 31 | 131311 |
| 32 | 132321 |
[1001,1111,1221,1331,1441,1551,1661,1771,1881, 1991,110101,111111,112121,113131,114141,115151, 116161,117171,118181,119191,120201,121211,122221, 123231,124241,125251,126261,127271,128281,129291, 130301,131311,132321] |