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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 6 |
| 3 | 12 |
| 4 | 20 |
| 5 | 56 |
| 6 | 72 |
| 7 | 240 |
| 8 | 272 |
| 9 | 992 |
| 10 | 1056 |
| 11 | 4032 |
| 12 | 4160 |
| 13 | 16256 |
| 14 | 16512 |
| 15 | 65280 |
| 16 | 65792 |
| 17 | 261632 |
| 18 | 262656 |
| 19 | 1047552 |
| 20 | 1049600 |
| 21 | 4192256 |
| 22 | 4196352 |
| 23 | 16773120 |
| 24 | 16781312 |
| 25 | 67100672 |
| 26 | 67117056 |
| 27 | 268419072 |
| 28 | 268451840 |
| 29 | 1073709056 |
| 30 | 1073774592 |
| 31 | 4294901760 |
| 32 | 4295032832 |
| 33 | 17179738112 |
| 34 | 17180000256 |
[2,6,12,20,56,72,240,272,992,1056,4032,4160,16256, 16512,65280,65792,261632,262656,1047552,1049600, 4192256,4196352,16773120,16781312,67100672, 67117056,268419072,268451840,1073709056, 1073774592,4294901760,4295032832,17179738112, 17180000256] |