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