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| n | a(n) |
|---|---|
| 1 | 21 |
| 2 | 25 |
| 3 | 43 |
| 4 | 49 |
| 5 | 63 |
| 6 | 67 |
| 7 | 69 |
| 8 | 87 |
| 9 | 201 |
| 10 | 205 |
| 11 | 223 |
| 12 | 241 |
| 13 | 261 |
| 14 | 267 |
| 15 | 283 |
| 16 | 285 |
| 17 | 289 |
| 18 | 409 |
| 19 | 421 |
| 20 | 427 |
| 21 | 429 |
| 22 | 463 |
| 23 | 483 |
| 24 | 487 |
| 25 | 489 |
| 26 | 601 |
| 27 | 621 |
| 28 | 643 |
| 29 | 645 |
| 30 | 685 |
| 31 | 801 |
| 32 | 805 |
| 33 | 823 |
| 34 | 841 |
| 35 | 867 |
| 36 | 883 |
| 37 | 885 |
| 38 | 2001 |
| 39 | 2023 |
| 40 | 2065 |
| 41 | 2067 |
| 42 | 2083 |
| 43 | 2085 |
| 44 | 2209 |
| 45 | 2221 |
| 46 | 2281 |
| 47 | 2283 |
| 48 | 2403 |
| 49 | 2407 |
| 50 | 2409 |
| 51 | 2427 |
| 52 | 2445 |
| 53 | 2461 |
| 54 | 2467 |
[21,25,43,49,63,67,69,87,201,205,223,241,261,267, 283,285,289,409,421,427,429,463,483,487,489,601, 621,643,645,685,801,805,823,841,867,883,885,2001, 2023,2065,2067,2083,2085,2209,2221,2281,2283,2403, 2407,2409,2427,2445,2461,2467] |