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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 7 |
| 3 | 0 |
| 4 | 31 |
| 5 | 0 |
| 6 | 127 |
| 7 | 0 |
| 8 | 511 |
| 9 | 0 |
| 10 | 2047 |
| 11 | 0 |
| 12 | 8191 |
| 13 | 768 |
| 14 | 32767 |
| 15 | 16128 |
| 16 | 115711 |
| 17 | 13056 |
| 18 | 520191 |
| 19 | 65280 |
| 20 | 2032639 |
| 21 | 61440 |
| 22 | 8327167 |
| 23 | 3207168 |
| 24 | 33427455 |
| 25 | 12840960 |
| 26 | 133959679 |
| 27 | 59240448 |
| 28 | 502796287 |
| 29 | 85979904 |
| 30 | 2139361279 |
| 31 | 117427968 |
| 32 | 8574268415 |
| 33 | 2063467264 |
| 34 | 32736804863 |
[1,0,7,0,31,0,127,0,511,0,2047,0,8191,768,32767, 16128,115711,13056,520191,65280,2032639,61440, 8327167,3207168,33427455,12840960,133959679, 59240448,502796287,85979904,2139361279,117427968, 8574268415,2063467264,32736804863] |