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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 3 |
| 3 | 5 |
| 4 | 17 |
| 5 | 191 |
| 6 | 257 |
| 7 | 1009 |
| 8 | 4561 |
| 9 | 4591 |
| 10 | 21601 |
| 11 | 57601 |
| 12 | 54121 |
| 13 | 86677 |
| 14 | 176401 |
| 15 | 415801 |
| 16 | 291721 |
| 17 | 950041 |
| 18 | 1259701 |
| 19 | 3049201 |
| 20 | 1670761 |
| 21 | 6098401 |
| 22 | 3880801 |
| 23 | 5654881 |
| 24 | 13759201 |
| 25 | 18618601 |
| 26 | 14414401 |
| 27 | 18960481 |
| 28 | 15135121 |
| 29 | 31600801 |
| 30 | 45405361 |
| 31 | 35814241 |
[2,3,5,17,191,257,1009,4561,4591,21601,57601, 54121,86677,176401,415801,291721,950041,1259701, 3049201,1670761,6098401,3880801,5654881,13759201, 18618601,14414401,18960481,15135121,31600801, 45405361,35814241] |