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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 0 |
| 4 | 4 |
| 5 | 4 |
| 6 | 16 |
| 7 | 24 |
| 8 | 71 |
| 9 | 128 |
| 10 | 328 |
| 11 | 650 |
| 12 | 1552 |
| 13 | 3232 |
| 14 | 7437 |
| 15 | 15904 |
| 16 | 35884 |
| 17 | 77840 |
| 18 | 173792 |
| 19 | 379896 |
| 20 | 843411 |
| 21 | 1851264 |
| 22 | 4097552 |
| 23 | 9014038 |
| 24 | 19918944 |
| 25 | 43871360 |
| 26 | 96860441 |
| 27 | 213472064 |
| 28 | 471086932 |
| 29 | 1038595100 |
| 30 | 2291372912 |
| 31 | 5052682904 |
| 32 | 11145821407 |
| 33 | 24580005376 |
| 34 | 54217564504 |
| 35 | 119573069218 |
[1,0,4,4,16,24,71,128,328,650,1552,3232,7437, 15904,35884,77840,173792,379896,843411,1851264, 4097552,9014038,19918944,43871360,96860441, 213472064,471086932,1038595100,2291372912, 5052682904,11145821407,24580005376,54217564504, 119573069218] |