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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 3 |
| 5 | 4 |
| 6 | 4 |
| 7 | 5 |
| 8 | 5 |
| 9 | 6 |
| 10 | 6 |
| 11 | 7 |
| 12 | 7 |
| 13 | 8 |
| 14 | 8 |
| 15 | 9 |
| 16 | 9 |
| 17 | 10 |
| 18 | 10 |
| 19 | 12 |
| 20 | 12 |
| 21 | 14 |
| 22 | 14 |
| 23 | 16 |
| 24 | 16 |
| 25 | 18 |
| 26 | 18 |
| 27 | 20 |
| 28 | 21 |
| 29 | 21 |
| 30 | 23 |
| 31 | 23 |
| 32 | 25 |
| 33 | 25 |
| 34 | 27 |
| 35 | 27 |
| 36 | 29 |
| 37 | 29 |
| 38 | 31 |
| 39 | 32 |
| 40 | 32 |
| 41 | 34 |
| 42 | 34 |
| 43 | 36 |
| 44 | 36 |
| 45 | 38 |
| 46 | 38 |
| 47 | 40 |
| 48 | 41 |
| 49 | 41 |
| 50 | 43 |
| 51 | 43 |
| 52 | 45 |
| 53 | 45 |
| 54 | 47 |
| 55 | 47 |
| 56 | 49 |
| 57 | 49 |
| 58 | 51 |
| 59 | 52 |
| 60 | 52 |
| 61 | 54 |
| 62 | 54 |
| 63 | 56 |
| 64 | 56 |
| 65 | 58 |
| 66 | 58 |
| 67 | 60 |
| 68 | 61 |
| 69 | 61 |
| 70 | 63 |
| 71 | 63 |
[1,2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,12,12,14, 14,16,16,18,18,20,21,21,23,23,25,25,27,27,29,29, 31,32,32,34,34,36,36,38,38,40,41,41,43,43,45,45, 47,47,49,49,51,52,52,54,54,56,56,58,58,60,61,61, 63,63] |