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| n | a(n) |
|---|---|
| 0 | -1 |
| 1 | -1 |
| 2 | 0 |
| 3 | -1 |
| 4 | 0 |
| 5 | 6 |
| 6 | -1 |
| 7 | 0 |
| 8 | 15 |
| 9 | 20 |
| 10 | -1 |
| 11 | 0 |
| 12 | 27 |
| 13 | 64 |
| 14 | 45 |
| 15 | -1 |
| 16 | 0 |
| 17 | 42 |
| 18 | 140 |
| 19 | 175 |
| 20 | 84 |
| 21 | -1 |
| 22 | 0 |
| 23 | 60 |
| 24 | 256 |
| 25 | 450 |
| 26 | 384 |
| 27 | 140 |
| 28 | -1 |
| 29 | 0 |
| 30 | 81 |
| 31 | 420 |
| 32 | 945 |
| 33 | 1134 |
| 34 | 735 |
| 35 | 216 |
| 36 | -1 |
| 37 | 0 |
| 38 | 105 |
| 39 | 640 |
| 40 | 1750 |
| 41 | 2688 |
| 42 | 2450 |
| 43 | 1280 |
| 44 | 315 |
| 45 | -1 |
| 46 | 0 |
| 47 | 132 |
| 48 | 924 |
| 49 | 2970 |
| 50 | 5544 |
| 51 | 6468 |
| 52 | 4752 |
| 53 | 2079 |
| 54 | 440 |
| 55 | -1 |
| 56 | 0 |
| 57 | 162 |
| 58 | 1280 |
| 59 | 4725 |
| 60 | 10368 |
| 61 | 14700 |
| 62 | 13824 |
| 63 | 8505 |
| 64 | 3200 |
| 65 | 594 |
[-1,-1,0,-1,0,6,-1,0,15,20,-1,0,27,64,45,-1,0,42, 140,175,84,-1,0,60,256,450,384,140,-1,0,81,420, 945,1134,735,216,-1,0,105,640,1750,2688,2450,1280, 315,-1,0,132,924,2970,5544,6468,4752,2079,440,-1, 0,162,1280,4725,10368,14700,13824,8505,3200,594] |