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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 5 |
| 5 | 25 |
| 6 | 31 |
| 7 | 217 |
| 8 | 209 |
| 9 | 1881 |
| 10 | 1891 |
| 11 | 20801 |
| 12 | 20789 |
| 13 | 270257 |
| 14 | 270271 |
| 15 | 4054065 |
| 16 | 4054049 |
| 17 | 68918833 |
| 18 | 68918851 |
| 19 | 1309458169 |
| 20 | 1309458149 |
| 21 | 27498621129 |
| 22 | 27498621151 |
| 23 | 632468286473 |
| 24 | 632468286449 |
| 25 | 15811707161225 |
| 26 | 15811707161251 |
[1,3,9,5,25,31,217,209,1881,1891,20801,20789, 270257,270271,4054065,4054049,68918833,68918851, 1309458169,1309458149,27498621129,27498621151, 632468286473,632468286449,15811707161225, 15811707161251] |