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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 6 |
| 3 | 45 |
| 4 | -1 |
| 5 | 15 |
| 6 | 36 |
| 7 | 21 |
| 8 | 120 |
| 9 | -1 |
| 10 | 210 |
| 11 | 66 |
| 12 | 36 |
| 13 | 78 |
| 14 | 210 |
| 15 | 45 |
| 16 | -1 |
| 17 | 1326 |
| 18 | 378 |
| 19 | 190 |
| 20 | 120 |
| 21 | 210 |
| 22 | 66 |
| 23 | 1035 |
| 24 | 4560 |
| 25 | -1 |
| 26 | 78 |
| 27 | 1485 |
| 28 | 1540 |
| 29 | 435 |
| 30 | 300 |
| 31 | 465 |
| 32 | 902496 |
| 33 | 1485 |
| 34 | 3570 |
| 35 | 105 |
| 36 | -1 |
| 37 | 17205 |
| 38 | 4560 |
| 39 | 2145 |
| 40 | 120 |
| 41 | 861 |
| 42 | 630 |
| 43 | 903 |
| 44 | 157080 |
| 45 | 4095 |
| 46 | 276 |
| 47 | 9870 |
| 48 | 41328 |
| 49 | -1 |
| 50 | 300 |
| 51 | 153 |
| 52 | 780 |
| 53 | 5565 |
| 54 | 1185030 |
[1,6,45,-1,15,36,21,120,-1,210,66,36,78,210,45,-1, 1326,378,190,120,210,66,1035,4560,-1,78,1485,1540, 435,300,465,902496,1485,3570,105,-1,17205,4560, 2145,120,861,630,903,157080,4095,276,9870,41328, -1,300,153,780,5565,1185030] |