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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 20 |
| 4 | 21 |
| 5 | 23 |
| 6 | 24 |
| 7 | 202 |
| 8 | 204 |
| 9 | 210 |
| 10 | 212 |
| 11 | 214 |
| 12 | 216 |
| 13 | 232 |
| 14 | 234 |
| 15 | 240 |
| 16 | 242 |
| 17 | 244 |
| 18 | 246 |
| 19 | 2020 |
| 20 | 2022 |
| 21 | 2023 |
| 22 | 2025 |
| 23 | 2026 |
| 24 | 2028 |
| 25 | 2040 |
| 26 | 2042 |
| 27 | 2043 |
| 28 | 2045 |
| 29 | 2046 |
| 30 | 2048 |
| 31 | 2100 |
| 32 | 2102 |
| 33 | 2103 |
| 34 | 2105 |
| 35 | 2106 |
| 36 | 2108 |
| 37 | 2120 |
| 38 | 2121 |
| 39 | 2122 |
| 40 | 2123 |
| 41 | 2125 |
| 42 | 2126 |
| 43 | 2127 |
| 44 | 2128 |
| 45 | 2140 |
| 46 | 2142 |
| 47 | 2143 |
[0,2,20,21,23,24,202,204,210,212,214,216,232,234, 240,242,244,246,2020,2022,2023,2025,2026,2028, 2040,2042,2043,2045,2046,2048,2100,2102,2103,2105, 2106,2108,2120,2121,2122,2123,2125,2126,2127,2128, 2140,2142,2143] |