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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 0 |
| 4 | -4 |
| 5 | 0 |
| 6 | 16 |
| 7 | 0 |
| 8 | -80 |
| 9 | 0 |
| 10 | 448 |
| 11 | 0 |
| 12 | -2688 |
| 13 | 0 |
| 14 | 16896 |
| 15 | 0 |
| 16 | -109824 |
| 17 | 0 |
| 18 | 732160 |
| 19 | 0 |
| 20 | -4978688 |
| 21 | 0 |
| 22 | 34398208 |
| 23 | 0 |
| 24 | -240787456 |
| 25 | 0 |
| 26 | 1704034304 |
| 27 | 0 |
| 28 | -12171673600 |
| 29 | 0 |
| 30 | 87636049920 |
| 31 | 0 |
| 32 | -635361361920 |
| 33 | 0 |
| 34 | 4634400522240 |
| 35 | 0 |
| 36 | -33985603829760 |
| 37 | 0 |
| 38 | 250420238745600 |
| 39 | 0 |
| 40 | -1853109766717440 |
[1,1,2,0,-4,0,16,0,-80,0,448,0,-2688,0,16896,0, -109824,0,732160,0,-4978688,0,34398208,0, -240787456,0,1704034304,0,-12171673600,0, 87636049920,0,-635361361920,0,4634400522240,0, -33985603829760,0,250420238745600,0, -1853109766717440] |