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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 5 |
| 5 | 8 |
| 6 | 12 |
| 7 | 20 |
| 8 | 49 |
| 9 | 64 |
| 10 | 304 |
| 11 | 672 |
| 12 | 1204 |
| 13 | 2648 |
| 14 | 3852 |
| 15 | 9320 |
| 16 | 18297 |
| 17 | 32960 |
| 18 | 75472 |
| 19 | 146392 |
| 20 | 304920 |
| 21 | 577336 |
| 22 | 1211144 |
| 23 | 2034072 |
| 24 | 4801892 |
| 25 | 7637392 |
| 26 | 18795944 |
| 27 | 33811680 |
| 28 | 71566612 |
| 29 | 139144320 |
| 30 | 285508328 |
| 31 | 569229920 |
| 32 | 1069209737 |
| 33 | 2314296064 |
| 34 | 4167725024 |
| 35 | 8567738280 |
| 36 | 16894013736 |
| 37 | 33135107200 |
| 38 | 68279466472 |
| 39 | 121133055024 |
[0,0,1,0,5,8,12,20,49,64,304,672,1204,2648,3852, 9320,18297,32960,75472,146392,304920,577336, 1211144,2034072,4801892,7637392,18795944,33811680, 71566612,139144320,285508328,569229920,1069209737, 2314296064,4167725024,8567738280,16894013736, 33135107200,68279466472,121133055024] |