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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 11 |
| 3 | 22 |
| 4 | 122 |
| 5 | 223 |
| 6 | 333 |
| 7 | 444 |
| 8 | 1444 |
| 9 | 2445 |
| 10 | 3455 |
| 11 | 4466 |
| 12 | 5566 |
| 13 | 6667 |
| 14 | 7777 |
| 15 | 8888 |
| 16 | 18888 |
| 17 | 28889 |
| 18 | 38899 |
| 19 | 48910 |
| 20 | 59010 |
| 21 | 69111 |
| 22 | 79221 |
| 23 | 89332 |
| 24 | 100332 |
| 25 | 111333 |
| 26 | 122343 |
| 27 | 133354 |
| 28 | 144454 |
| 29 | 155555 |
| 30 | 166665 |
| 31 | 177776 |
| 32 | 277776 |
| 33 | 377777 |
| 34 | 477787 |
| 35 | 577798 |
| 36 | 677898 |
| 37 | 777999 |
| 38 | 878109 |
[0,1,11,22,122,223,333,444,1444,2445,3455,4466, 5566,6667,7777,8888,18888,28889,38899,48910,59010, 69111,79221,89332,100332,111333,122343,133354, 144454,155555,166665,177776,277776,377777,477787, 577798,677898,777999,878109] |