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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | -1 |
| 2 | 2 |
| 3 | 3 |
| 4 | -1 |
| 5 | 6 |
| 6 | -1 |
| 7 | 10 |
| 8 | 15 |
| 9 | 14 |
| 10 | 30 |
| 11 | 11 |
| 12 | 42 |
| 13 | 22 |
| 14 | 70 |
| 15 | 105 |
| 16 | 66 |
| 17 | 210 |
| 18 | 110 |
| 19 | 165 |
| 20 | 154 |
| 21 | 330 |
| 22 | 182 |
| 23 | 462 |
| 24 | 170 |
| 25 | 770 |
| 26 | 1155 |
| 27 | 910 |
| 28 | 2310 |
| 29 | 858 |
| 30 | 2730 |
| 31 | 1430 |
| 32 | 2145 |
| 33 | 2002 |
| 34 | 4290 |
| 35 | 1870 |
| 36 | 6006 |
| 37 | 2618 |
| 38 | 10010 |
| 39 | 15015 |
| 40 | 7854 |
| 41 | 30030 |
| 42 | 13090 |
| 43 | 19635 |
| 44 | 15470 |
| 45 | 39270 |
| 46 | 17290 |
| 47 | 46410 |
| 48 | 24310 |
| 49 | 51870 |
[1,-1,2,3,-1,6,-1,10,15,14,30,11,42,22,70,105,66, 210,110,165,154,330,182,462,170,770,1155,910,2310, 858,2730,1430,2145,2002,4290,1870,6006,2618,10010, 15015,7854,30030,13090,19635,15470,39270,17290, 46410,24310,51870] |