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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 12 |
| 6 | 0 |
| 7 | 1 |
| 8 | 60 |
| 9 | 360 |
| 10 | 0 |
| 11 | 1 |
| 12 | 252 |
| 13 | 5040 |
| 14 | 20160 |
| 15 | 0 |
| 16 | 1 |
| 17 | 1020 |
| 18 | 52920 |
| 19 | 604800 |
| 20 | 1814400 |
| 21 | 0 |
| 22 | 1 |
| 23 | 4092 |
| 24 | 506880 |
| 25 | 12640320 |
| 26 | 99792000 |
| 27 | 239500800 |
| 28 | 0 |
| 29 | 1 |
| 30 | 16380 |
| 31 | 4684680 |
| 32 | 230630400 |
| 33 | 3632428800 |
| 34 | 21794572800 |
| 35 | 43589145600 |
| 36 | 0 |
| 37 | 1 |
| 38 | 65532 |
| 39 | 42653520 |
| 40 | 3952428480 |
[1,0,1,0,1,12,0,1,60,360,0,1,252,5040,20160,0,1, 1020,52920,604800,1814400,0,1,4092,506880, 12640320,99792000,239500800,0,1,16380,4684680, 230630400,3632428800,21794572800,43589145600,0,1, 65532,42653520,3952428480] |