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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 3 |
| 4 | 0 |
| 5 | 63 |
| 6 | 0 |
| 7 | 255 |
| 8 | 0 |
| 9 | 1023 |
| 10 | 0 |
| 11 | 4095 |
| 12 | 0 |
| 13 | 16383 |
| 14 | 0 |
| 15 | 65535 |
| 16 | 0 |
| 17 | 262143 |
| 18 | 0 |
| 19 | 1048575 |
| 20 | 0 |
| 21 | 4194303 |
| 22 | 0 |
| 23 | 16777215 |
| 24 | 0 |
| 25 | 67108863 |
| 26 | 0 |
| 27 | 268435455 |
| 28 | 0 |
| 29 | 1073741823 |
| 30 | 0 |
| 31 | 4294967295 |
| 32 | 0 |
| 33 | 17179869183 |
| 34 | 0 |
| 35 | 68719476735 |
| 36 | 0 |
| 37 | 274877906943 |
| 38 | 0 |
| 39 | 1099511627775 |
| 40 | 0 |
| 41 | 4398046511103 |
| 42 | 0 |
[1,1,4,3,0,63,0,255,0,1023,0,4095,0,16383,0,65535, 0,262143,0,1048575,0,4194303,0,16777215,0, 67108863,0,268435455,0,1073741823,0,4294967295,0, 17179869183,0,68719476735,0,274877906943,0, 1099511627775,0,4398046511103,0] |