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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 5 |
| 7 | 6 |
| 8 | 7 |
| 9 | 8 |
| 10 | 9 |
| 11 | 122 |
| 12 | 202 |
| 13 | 212 |
| 14 | 220 |
| 15 | 221 |
| 16 | 244 |
| 17 | 424 |
| 18 | 442 |
| 19 | 1000 |
| 20 | 1001 |
| 21 | 1010 |
| 22 | 1011 |
| 23 | 1100 |
| 24 | 1101 |
| 25 | 1110 |
| 26 | 1111 |
| 27 | 2222 |
| 28 | 3333 |
| 29 | 3444 |
| 30 | 4344 |
| 31 | 4434 |
| 32 | 4443 |
| 33 | 4444 |
| 34 | 5555 |
| 35 | 6666 |
| 36 | 6677 |
| 37 | 6767 |
| 38 | 6776 |
| 39 | 6888 |
| 40 | 7667 |
| 41 | 7676 |
| 42 | 7766 |
| 43 | 7777 |
| 44 | 8688 |
| 45 | 8868 |
| 46 | 8886 |
| 47 | 8888 |
| 48 | 9999 |
[0,1,2,3,4,5,6,7,8,9,122,202,212,220,221,244,424, 442,1000,1001,1010,1011,1100,1101,1110,1111,2222, 3333,3444,4344,4434,4443,4444,5555,6666,6677,6767, 6776,6888,7667,7676,7766,7777,8688,8868,8886,8888, 9999] |