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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 4 |
| 3 | 6 |
| 4 | 48 |
| 5 | 0 |
| 6 | 360 |
| 7 | 420 |
| 8 | 1680 |
| 9 | 0 |
| 10 | 25200 |
| 11 | 0 |
| 12 | 332640 |
| 13 | 0 |
| 14 | 0 |
| 15 | 360360 |
| 16 | 11531520 |
| 17 | 0 |
| 18 | 220540320 |
| 19 | 0 |
| 20 | 0 |
| 21 | 0 |
| 22 | 5121436320 |
| 23 | 0 |
| 24 | 21416915520 |
| 25 | 0 |
| 26 | 53542288800 |
| 27 | 0 |
| 28 | 2248776129600 |
| 29 | 0 |
| 30 | 69872686884000 |
| 31 | 72201776446800 |
| 32 | 0 |
| 33 | 0 |
| 34 | 0 |
[0,1,4,6,48,0,360,420,1680,0,25200,0,332640,0,0, 360360,11531520,0,220540320,0,0,0,5121436320,0, 21416915520,0,53542288800,0,2248776129600,0, 69872686884000,72201776446800,0,0,0] |