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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 5 |
| 4 | 15 |
| 5 | 255 |
| 6 | 65535 |
| 7 | 2200694 |
| 8 | 2619705 |
| 9 | 6372794 |
| 10 | 40588485 |
| 11 | 76466985 |
| 12 | 81591194 |
| 13 | 118018094 |
| 14 | 206569605 |
| 15 | 470542485 |
| 16 | 525644385 |
| 17 | 726638834 |
| 18 | 791937614 |
| 19 | 971122514 |
| 20 | 991172805 |
[1,3,5,15,255,65535,2200694,2619705,6372794, 40588485,76466985,81591194,118018094,206569605, 470542485,525644385,726638834,791937614,971122514, 991172805] |