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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 6 |
| 4 | 0 |
| 5 | 1 |
| 6 | 0 |
| 7 | 18 |
| 8 | 0 |
| 9 | 1 |
| 10 | 96 |
| 11 | 0 |
| 12 | 36 |
| 13 | 0 |
| 14 | 1 |
| 15 | 0 |
| 16 | 480 |
| 17 | 0 |
| 18 | 60 |
| 19 | 0 |
| 20 | 1 |
| 21 | 2880 |
| 22 | 0 |
| 23 | 1440 |
| 24 | 0 |
| 25 | 90 |
| 26 | 0 |
| 27 | 1 |
| 28 | 0 |
| 29 | 20160 |
| 30 | 0 |
| 31 | 3360 |
| 32 | 0 |
| 33 | 126 |
| 34 | 0 |
| 35 | 1 |
| 36 | 161280 |
| 37 | 0 |
| 38 | 80640 |
| 39 | 0 |
| 40 | 6720 |
| 41 | 0 |
| 42 | 168 |
| 43 | 0 |
| 44 | 1 |
| 45 | 0 |
| 46 | 1451520 |
| 47 | 0 |
| 48 | 241920 |
| 49 | 0 |
| 50 | 12096 |
| 51 | 0 |
| 52 | 216 |
| 53 | 0 |
| 54 | 1 |
| 55 | 14515200 |
| 56 | 0 |
| 57 | 7257600 |
| 58 | 0 |
| 59 | 604800 |
| 60 | 0 |
| 61 | 20160 |
| 62 | 0 |
| 63 | 270 |
| 64 | 0 |
| 65 | 1 |
[0,1,6,0,1,0,18,0,1,96,0,36,0,1,0,480,0,60,0,1, 2880,0,1440,0,90,0,1,0,20160,0,3360,0,126,0,1, 161280,0,80640,0,6720,0,168,0,1,0,1451520,0, 241920,0,12096,0,216,0,1,14515200,0,7257600,0, 604800,0,20160,0,270,0,1] |