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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 3 |
| 6 | 3 |
| 7 | 4 |
| 8 | 4 |
| 9 | 5 |
| 10 | 6 |
| 11 | 6 |
| 12 | 7 |
| 13 | 7 |
| 14 | 8 |
| 15 | 9 |
| 16 | 9 |
| 17 | 10 |
| 18 | 10 |
| 19 | 11 |
| 20 | 12 |
| 21 | 12 |
| 22 | 13 |
| 23 | 13 |
| 24 | 14 |
| 25 | 14 |
| 26 | 15 |
| 27 | 16 |
| 28 | 16 |
| 29 | 17 |
| 30 | 17 |
| 31 | 18 |
| 32 | 19 |
| 33 | 19 |
| 34 | 20 |
| 35 | 20 |
| 36 | 21 |
| 37 | 21 |
| 38 | 22 |
| 39 | 23 |
| 40 | 23 |
| 41 | 24 |
| 42 | 24 |
| 43 | 25 |
| 44 | 26 |
| 45 | 26 |
| 46 | 27 |
| 47 | 27 |
| 48 | 28 |
| 49 | 28 |
| 50 | 29 |
| 51 | 30 |
| 52 | 30 |
| 53 | 31 |
| 54 | 31 |
| 55 | 32 |
| 56 | 33 |
| 57 | 33 |
| 58 | 34 |
| 59 | 34 |
| 60 | 35 |
| 61 | 36 |
| 62 | 36 |
| 63 | 37 |
| 64 | 37 |
| 65 | 38 |
| 66 | 38 |
| 67 | 39 |
| 68 | 40 |
| 69 | 40 |
| 70 | 41 |
| 71 | 41 |
| 72 | 42 |
| 73 | 43 |
| 74 | 43 |
| 75 | 44 |
| 76 | 44 |
| 77 | 45 |
| 78 | 45 |
| 79 | 46 |
| 80 | 47 |
| 81 | 47 |
[0,1,2,2,3,3,4,4,5,6,6,7,7,8,9,9,10,10,11,12,12, 13,13,14,14,15,16,16,17,17,18,19,19,20,20,21,21, 22,23,23,24,24,25,26,26,27,27,28,28,29,30,30,31, 31,32,33,33,34,34,35,36,36,37,37,38,38,39,40,40, 41,41,42,43,43,44,44,45,45,46,47,47] |