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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 2 |
| 4 | 0 |
| 5 | 0 |
| 6 | 0 |
| 7 | 360 |
| 8 | 0 |
| 9 | 1680 |
| 10 | 0 |
| 11 | 35280 |
| 12 | 0 |
| 13 | 332640 |
| 14 | 0 |
| 15 | 0 |
| 16 | 0 |
| 17 | 8648640 |
| 18 | 0 |
| 19 | 306306000 |
| 20 | 0 |
| 21 | 0 |
| 22 | 0 |
| 23 | 232792560 |
| 24 | 0 |
| 25 | 0 |
| 26 | 0 |
| 27 | 26771144400 |
| 28 | 0 |
| 29 | 481880599200 |
| 30 | 0 |
| 31 | 41923612130400 |
| 32 | 0 |
| 33 | 0 |
| 34 | 0 |
| 35 | 0 |
| 36 | 0 |
| 37 | 5487335009956800 |
| 38 | 0 |
| 39 | 0 |
| 40 | 0 |
| 41 | 245774847024907200 |
| 42 | 0 |
| 43 | 8105227020364874400 |
| 44 | 0 |
| 45 | 0 |
| 46 | 0 |
| 47 | 452140231622516236800 |
| 48 | 0 |
| 49 | 3984485791173424336800 |
| 50 | 0 |
[1,0,2,0,0,0,360,0,1680,0,35280,0,332640,0,0,0, 8648640,0,306306000,0,0,0,232792560,0,0,0, 26771144400,0,481880599200,0,41923612130400,0,0,0, 0,0,5487335009956800,0,0,0,245774847024907200,0, 8105227020364874400,0,0,0,452140231622516236800,0, 3984485791173424336800,0] |