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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 3 |
| 4 | 5 |
| 5 | 4 |
| 6 | 11 |
| 7 | 10 |
| 8 | 16 |
| 9 | 25 |
| 10 | 31 |
| 11 | 41 |
| 12 | -1 |
| 13 | 57 |
| 14 | 56 |
| 15 | 75 |
| 16 | 73 |
| 17 | 80 |
| 18 | -1 |
| 19 | 108 |
| 20 | 110 |
| 21 | 142 |
| 22 | 112 |
| 23 | 149 |
| 24 | 148 |
| 25 | 155 |
| 26 | 154 |
| 27 | 168 |
| 28 | 194 |
| 29 | 203 |
| 30 | 221 |
| 31 | 238 |
| 32 | -1 |
| 33 | 271 |
| 34 | -1 |
| 35 | -1 |
| 36 | 308 |
| 37 | -1 |
| 38 | 360 |
| 39 | 414 |
| 40 | 416 |
| 41 | 437 |
| 42 | -1 |
| 43 | -1 |
| 44 | 484 |
| 45 | -1 |
| 46 | -1 |
| 47 | 529 |
| 48 | -1 |
| 49 | 660 |
| 50 | -1 |
| 51 | 740 |
| 52 | 944 |
| 53 | 760 |
| 54 | 869 |
| 55 | 916 |
| 56 | 984 |
| 57 | -1 |
| 58 | 1010 |
| 59 | 1016 |
| 60 | 1020 |
| 61 | -1 |
| 62 | 1032 |
| 63 | -1 |
| 64 | 1193 |
| 65 | 1219 |
| 66 | 1160 |
| 67 | 1329 |
| 68 | 1264 |
| 69 | 1331 |
| 70 | 1200 |
| 71 | 1426 |
| 72 | 1303 |
| 73 | 1350 |
| 74 | 1369 |
| 75 | 1473 |
| 76 | 1543 |
[1,3,5,4,11,10,16,25,31,41,-1,57,56,75,73,80,-1, 108,110,142,112,149,148,155,154,168,194,203,221, 238,-1,271,-1,-1,308,-1,360,414,416,437,-1,-1,484, -1,-1,529,-1,660,-1,740,944,760,869,916,984,-1, 1010,1016,1020,-1,1032,-1,1193,1219,1160,1329, 1264,1331,1200,1426,1303,1350,1369,1473,1543] |