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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 15 |
| 3 | 63 |
| 4 | 255 |
| 5 | 1023 |
| 6 | 4095 |
| 7 | 16383 |
| 8 | 65535 |
| 9 | 262143 |
| 10 | 1048575 |
| 11 | 4194303 |
| 12 | 16777215 |
| 13 | 67108863 |
| 14 | 268435455 |
| 15 | 1073741823 |
| 16 | 4294967295 |
| 17 | 17179869183 |
| 18 | 68719476735 |
| 19 | 274877906943 |
| 20 | 1099511627775 |
| 21 | 4398046511103 |
| 22 | 17592186044415 |
| 23 | 70368744177663 |
[1,3,15,63,255,1023,4095,16383,65535,262143, 1048575,4194303,16777215,67108863,268435455, 1073741823,4294967295,17179869183,68719476735, 274877906943,1099511627775,4398046511103, 17592186044415,70368744177663] |