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| n | a(n) |
|---|---|
| 1 | 31 |
| 2 | 71 |
| 3 | 311 |
| 4 | 551 |
| 5 | 1151 |
| 6 | 14831 |
| 7 | 45791 |
| 8 | 455471 |
| 9 | 2035271 |
| 10 | 6345239 |
| 11 | 7241615 |
| 12 | 8290031 |
| 13 | 8329991 |
| 14 | 9086231 |
| 15 | 9324351 |
| 16 | 10449575 |
| 17 | 11497199 |
| 18 | 15454151 |
| 19 | 16515815 |
| 20 | 18337271 |
| 21 | 20650811 |
| 22 | 22946591 |
| 23 | 27609311 |
| 24 | 33220079 |
| 25 | 40487471 |
| 26 | 44106191 |
| 27 | 45015791 |
| 28 | 49021199 |
| 29 | 53315519 |
| 30 | 54536519 |
[31,71,311,551,1151,14831,45791,455471,2035271, 6345239,7241615,8290031,8329991,9086231,9324351, 10449575,11497199,15454151,16515815,18337271, 20650811,22946591,27609311,33220079,40487471, 44106191,45015791,49021199,53315519,54536519] |