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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 13 |
| 4 | 1 |
| 5 | 61 |
| 6 | 1 |
| 7 | 253 |
| 8 | 1 |
| 9 | 1021 |
| 10 | 1 |
| 11 | 4093 |
| 12 | 1 |
| 13 | 16381 |
| 14 | 1 |
| 15 | 65533 |
| 16 | 1 |
| 17 | 262141 |
| 18 | 1 |
| 19 | 1048573 |
| 20 | 1 |
| 21 | 4194301 |
| 22 | 1 |
| 23 | 16777213 |
| 24 | 1 |
| 25 | 67108861 |
| 26 | 1 |
| 27 | 268435453 |
| 28 | 1 |
| 29 | 1073741821 |
| 30 | 1 |
| 31 | 4294967293 |
| 32 | 1 |
| 33 | 17179869181 |
| 34 | 1 |
| 35 | 68719476733 |
| 36 | 1 |
| 37 | 274877906941 |
| 38 | 1 |
| 39 | 1099511627773 |
| 40 | 1 |
| 41 | 4398046511101 |
| 42 | 1 |
[1,1,1,13,1,61,1,253,1,1021,1,4093,1,16381,1, 65533,1,262141,1,1048573,1,4194301,1,16777213,1, 67108861,1,268435453,1,1073741821,1,4294967293,1, 17179869181,1,68719476733,1,274877906941,1, 1099511627773,1,4398046511101,1] |