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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 23 |
| 3 | 223 |
| 4 | 373 |
| 5 | 2237 |
| 6 | 2337 |
| 7 | 19373 |
| 8 | 22337 |
| 9 | 22373 |
| 10 | 23773 |
| 11 | 31373 |
| 12 | 23373 |
| 13 | 37337 |
| 14 | 223737 |
| 15 | 223773 |
| 16 | 223373 |
| 17 | 233137 |
| 18 | 233373 |
| 19 | 237337 |
| 20 | 1137337 |
| 21 | 1937337 |
| 22 | 1373373 |
| 23 | 2233733 |
| 24 | 2233137 |
| 25 | 373373 |
| 26 | 2233373 |
| 27 | 2337313 |
| 28 | 2237337 |
| 29 | 2237373 |
| 30 | 2337353 |
| 31 | 3733313 |
| 32 | 2331373 |
| 33 | 3137337 |
| 34 | 3137373 |
| 35 | 3373373 |
| 36 | 2337373 |
| 37 | 2337337 |
| 38 | 2373373 |
[2,23,223,373,2237,2337,19373,22337,22373,23773, 31373,23373,37337,223737,223773,223373,233137, 233373,237337,1137337,1937337,1373373,2233733, 2233137,373373,2233373,2337313,2237337,2237373, 2337353,3733313,2331373,3137337,3137373,3373373, 2337373,2337337,2373373] |