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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 2 |
| 4 | 4 |
| 5 | 4 |
| 6 | 0 |
| 7 | 10 |
| 8 | 32 |
| 9 | 30 |
| 10 | 0 |
| 11 | 94 |
| 12 | 344 |
| 13 | 316 |
| 14 | 0 |
| 15 | 1096 |
| 16 | 4096 |
| 17 | 3856 |
| 18 | 0 |
| 19 | 13798 |
| 20 | 52432 |
| 21 | 49940 |
| 22 | 0 |
| 23 | 182362 |
| 24 | 699072 |
| 25 | 671092 |
| 26 | 0 |
| 27 | 2485534 |
| 28 | 9586984 |
| 29 | 9256396 |
| 30 | 0 |
| 31 | 34636834 |
| 32 | 134217728 |
| 33 | 130150588 |
| 34 | 0 |
| 35 | 490853416 |
| 36 | 1908874584 |
| 37 | 1857283156 |
| 38 | 0 |
| 39 | 7048151672 |
| 40 | 27487790720 |
[1,0,2,4,4,0,10,32,30,0,94,344,316,0,1096,4096, 3856,0,13798,52432,49940,0,182362,699072,671092,0, 2485534,9586984,9256396,0,34636834,134217728, 130150588,0,490853416,1908874584,1857283156,0, 7048151672,27487790720] |