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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 5 |
| 3 | 13 |
| 4 | 17 |
| 5 | 51 |
| 6 | 85 |
| 7 | 193 |
| 8 | 257 |
| 9 | 769 |
| 10 | 1285 |
| 11 | 3281 |
| 12 | 4369 |
| 13 | 12289 |
| 14 | 21845 |
| 15 | 49601 |
| 16 | 65537 |
| 17 | 196611 |
| 18 | 327685 |
| 19 | 786433 |
| 20 | 1114129 |
| 21 | 3158273 |
| 22 | 5570645 |
| 23 | 12648641 |
| 24 | 16843009 |
| 25 | 50397953 |
| 26 | 84215045 |
| 27 | 202113281 |
| 28 | 286331153 |
| 29 | 805384193 |
| 30 | 1431655765 |
| 31 | 3221225473 |
| 32 | 8168859365 |
| 33 | 12952273921 |
[3,5,13,17,51,85,193,257,769,1285,3281,4369,12289, 21845,49601,65537,196611,327685,786433,1114129, 3158273,5570645,12648641,16843009,50397953, 84215045,202113281,286331153,805384193,1431655765, 3221225473,8168859365,12952273921] |