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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 24 |
| 4 | 56 |
| 5 | 128 |
| 6 | 384 |
| 7 | 832 |
| 8 | 1792 |
| 9 | 4608 |
| 10 | 9728 |
| 11 | 20480 |
| 12 | 49152 |
| 13 | 102400 |
| 14 | 212992 |
| 15 | 491520 |
| 16 | 1015808 |
| 17 | 2097152 |
| 18 | 4718592 |
| 19 | 9699328 |
| 20 | 19922944 |
| 21 | 44040192 |
| 22 | 90177536 |
| 23 | 184549376 |
| 24 | 402653184 |
| 25 | 822083584 |
| 26 | 1677721600 |
| 27 | 3623878656 |
| 28 | 7381975040 |
| 29 | 15032385536 |
| 30 | 32212254720 |
[0,1,4,24,56,128,384,832,1792,4608,9728,20480, 49152,102400,212992,491520,1015808,2097152, 4718592,9699328,19922944,44040192,90177536, 184549376,402653184,822083584,1677721600, 3623878656,7381975040,15032385536,32212254720] |