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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 1 |
| 3 | 4 |
| 4 | 3 |
| 5 | 6 |
| 6 | 5 |
| 7 | 8 |
| 8 | 7 |
| 9 | 10 |
| 10 | 9 |
| 11 | 20 |
| 12 | 30 |
| 13 | 22 |
| 14 | 23 |
| 15 | 24 |
| 16 | 25 |
| 17 | 26 |
| 18 | 27 |
| 19 | 28 |
| 20 | 11 |
| 21 | 33 |
| 22 | 13 |
| 23 | 14 |
| 24 | 15 |
| 25 | 16 |
| 26 | 17 |
| 27 | 18 |
| 28 | 19 |
| 29 | 31 |
| 30 | 12 |
| 31 | 29 |
| 32 | 40 |
| 33 | 21 |
| 34 | 50 |
| 35 | 41 |
| 36 | 42 |
| 37 | 44 |
| 38 | 45 |
| 39 | 46 |
| 40 | 32 |
| 41 | 35 |
| 42 | 36 |
| 43 | 51 |
| 44 | 37 |
| 45 | 38 |
| 46 | 39 |
| 47 | 52 |
| 48 | 53 |
| 49 | 55 |
| 50 | 34 |
| 51 | 43 |
| 52 | 47 |
| 53 | 48 |
| 54 | 60 |
| 55 | 49 |
| 56 | 70 |
| 57 | 61 |
| 58 | 62 |
| 59 | 63 |
| 60 | 54 |
| 61 | 57 |
| 62 | 58 |
| 63 | 59 |
| 64 | 71 |
| 65 | 72 |
| 66 | 73 |
| 67 | 80 |
| 68 | 74 |
| 69 | 75 |
| 70 | 56 |
| 71 | 64 |
| 72 | 65 |
[2,1,4,3,6,5,8,7,10,9,20,30,22,23,24,25,26,27,28, 11,33,13,14,15,16,17,18,19,31,12,29,40,21,50,41, 42,44,45,46,32,35,36,51,37,38,39,52,53,55,34,43, 47,48,60,49,70,61,62,63,54,57,58,59,71,72,73,80, 74,75,56,64,65] |