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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 1 |
| 3 | 12 |
| 4 | 3 |
| 5 | 56 |
| 6 | 7 |
| 7 | 240 |
| 8 | 15 |
| 9 | 992 |
| 10 | 31 |
| 11 | 4032 |
| 12 | 63 |
| 13 | 16256 |
| 14 | 127 |
| 15 | 65280 |
| 16 | 255 |
| 17 | 261632 |
| 18 | 511 |
| 19 | 1047552 |
| 20 | 1023 |
| 21 | 4192256 |
| 22 | 2047 |
| 23 | 16773120 |
| 24 | 4095 |
| 25 | 67100672 |
| 26 | 8191 |
| 27 | 268419072 |
| 28 | 16383 |
| 29 | 1073709056 |
| 30 | 32767 |
| 31 | 4294901760 |
| 32 | 65535 |
| 33 | 17179738112 |
| 34 | 131071 |
| 35 | 68719214592 |
| 36 | 262143 |
[1,2,1,12,3,56,7,240,15,992,31,4032,63,16256,127, 65280,255,261632,511,1047552,1023,4192256,2047, 16773120,4095,67100672,8191,268419072,16383, 1073709056,32767,4294901760,65535,17179738112, 131071,68719214592,262143] |