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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 4 |
| 6 | 1 |
| 7 | 2 |
| 8 | 46 |
| 9 | 46 |
| 10 | 2 |
| 11 | 8 |
| 12 | 384 |
| 13 | 996 |
| 14 | 384 |
| 15 | 8 |
| 16 | 28 |
| 17 | 2894 |
| 18 | 16860 |
| 19 | 16860 |
| 20 | 2894 |
| 21 | 28 |
| 22 | 94 |
| 23 | 20444 |
| 24 | 259040 |
| 25 | 592416 |
| 26 | 259040 |
| 27 | 20444 |
| 28 | 94 |
| 29 | 304 |
| 30 | 138944 |
| 31 | 3753846 |
| 32 | 18844474 |
| 33 | 18844474 |
| 34 | 3753846 |
| 35 | 138944 |
| 36 | 304 |
| 37 | 960 |
| 38 | 918744 |
| 39 | 52433492 |
| 40 | 566131860 |
| 41 | 1240628942 |
[0,0,0,1,4,1,2,46,46,2,8,384,996,384,8,28,2894, 16860,16860,2894,28,94,20444,259040,592416,259040, 20444,94,304,138944,3753846,18844474,18844474, 3753846,138944,304,960,918744,52433492,566131860, 1240628942] |