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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 11 |
| 5 | 22 |
| 6 | 101 |
| 7 | 111 |
| 8 | 121 |
| 9 | 202 |
| 10 | 212 |
| 11 | 222 |
| 12 | 1001 |
| 13 | 1111 |
| 14 | 1221 |
| 15 | 2002 |
| 16 | 2112 |
| 17 | 2222 |
| 18 | 10001 |
| 19 | 10101 |
| 20 | 10201 |
| 21 | 11011 |
| 22 | 11111 |
| 23 | 11211 |
| 24 | 12021 |
| 25 | 12121 |
| 26 | 12221 |
| 27 | 20002 |
| 28 | 20102 |
| 29 | 20202 |
| 30 | 21012 |
| 31 | 21112 |
| 32 | 21212 |
| 33 | 22022 |
| 34 | 22122 |
| 35 | 22222 |
| 36 | 100001 |
| 37 | 101101 |
| 38 | 102201 |
| 39 | 110011 |
| 40 | 111111 |
| 41 | 112211 |
| 42 | 120021 |
[0,1,2,11,22,101,111,121,202,212,222,1001,1111, 1221,2002,2112,2222,10001,10101,10201,11011,11111, 11211,12021,12121,12221,20002,20102,20202,21012, 21112,21212,22022,22122,22222,100001,101101, 102201,110011,111111,112211,120021] |