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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 23 |
| 3 | 25 |
| 4 | 27 |
| 5 | 29 |
| 6 | 51 |
| 7 | 56 |
| 8 | 201 |
| 9 | 209 |
| 10 | 227 |
| 11 | 229 |
| 12 | 241 |
| 13 | 243 |
| 14 | 261 |
| 15 | 263 |
| 16 | 287 |
| 17 | 289 |
| 18 | 551 |
| 19 | 2023 |
| 20 | 2027 |
| 21 | 2043 |
| 22 | 2047 |
| 23 | 2061 |
| 24 | 2069 |
| 25 | 2081 |
| 26 | 2089 |
| 27 | 2207 |
| 28 | 2209 |
| 29 | 2221 |
| 30 | 2223 |
| 31 | 2263 |
| 32 | 2267 |
| 33 | 2281 |
| 34 | 2287 |
| 35 | 2401 |
| 36 | 2407 |
| 37 | 2421 |
| 38 | 2423 |
| 39 | 2441 |
| 40 | 2449 |
| 41 | 2483 |
| 42 | 2489 |
| 43 | 2603 |
| 44 | 2609 |
[21,23,25,27,29,51,56,201,209,227,229,241,243,261, 263,287,289,551,2023,2027,2043,2047,2061,2069, 2081,2089,2207,2209,2221,2223,2263,2267,2281,2287, 2401,2407,2421,2423,2441,2449,2483,2489,2603,2609] |