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Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
Reminder: The OEIS is hiring a new managing editor, and the application deadline is January 26.
| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 23 |
| 3 | -1 |
| 4 | 223 |
| 5 | 22 |
| 6 | -1 |
| 7 | 2237 |
| 8 | 235 |
| 9 | 27 |
| 10 | -1 |
| 11 | 22273 |
| 12 | 2227 |
| 13 | 222 |
| 14 | 132 |
| 15 | -1 |
| 16 | 222323 |
| 17 | 22223 |
| 18 | 2222 |
| 19 | 225 |
| 20 | 32 |
| 21 | -1 |
| 22 | 2222273 |
| 23 | 222223 |
| 24 | 22222 |
| 25 | 2223 |
| 26 | 252 |
| 27 | 729 |
| 28 | -1 |
| 29 | 22222223 |
| 30 | 2222557 |
| 31 | 222227 |
| 32 | 22225 |
| 33 | 2322 |
| 34 | 352 |
| 35 | 192 |
| 36 | -1 |
| 37 | 222222227 |
| 38 | 22222237 |
| 39 | 2222222 |
| 40 | 222225 |
| 41 | 22232 |
| 42 | 2232 |
| 43 | 2352 |
| 44 | 2112 |
| 45 | -1 |
| 46 | 2222222377 |
| 47 | 222222223 |
[2,23,-1,223,22,-1,2237,235,27,-1,22273,2227,222, 132,-1,222323,22223,2222,225,32,-1,2222273,222223, 22222,2223,252,729,-1,22222223,2222557,222227, 22225,2322,352,192,-1,222222227,22222237,2222222, 222225,22232,2232,2352,2112,-1,2222222377, 222222223] |