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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 2 |
| 3 | 1 |
| 4 | 3 |
| 5 | 2 |
| 6 | 2 |
| 7 | 4 |
| 8 | 3 |
| 9 | 4 |
| 10 | 5 |
| 11 | 5 |
| 12 | 6 |
| 13 | 7 |
| 14 | 8 |
| 15 | 9 |
| 16 | 11 |
| 17 | 12 |
| 18 | 14 |
| 19 | 17 |
| 20 | 19 |
| 21 | 22 |
| 22 | 26 |
| 23 | 30 |
| 24 | 35 |
| 25 | 41 |
| 26 | 47 |
| 27 | 55 |
| 28 | 64 |
| 29 | 74 |
| 30 | 87 |
| 31 | 101 |
| 32 | 117 |
| 33 | 137 |
| 34 | 159 |
| 35 | 185 |
| 36 | 216 |
| 37 | 251 |
| 38 | 293 |
| 39 | 341 |
| 40 | 397 |
| 41 | 463 |
| 42 | 539 |
| 43 | 628 |
| 44 | 732 |
| 45 | 853 |
| 46 | 994 |
| 47 | 1158 |
| 48 | 1350 |
| 49 | 1573 |
| 50 | 1833 |
| 51 | 2136 |
| 52 | 2489 |
| 53 | 2901 |
| 54 | 3380 |
| 55 | 3939 |
| 56 | 4591 |
| 57 | 5349 |
| 58 | 6234 |
| 59 | 7265 |
| 60 | 8466 |
[2,2,1,3,2,2,4,3,4,5,5,6,7,8,9,11,12,14,17,19,22, 26,30,35,41,47,55,64,74,87,101,117,137,159,185, 216,251,293,341,397,463,539,628,732,853,994,1158, 1350,1573,1833,2136,2489,2901,3380,3939,4591,5349, 6234,7265,8466] |