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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 2 |
| 4 | 9 |
| 5 | 5 |
| 6 | 3 |
| 7 | 20 |
| 8 | 13 |
| 9 | 7 |
| 10 | 4 |
| 11 | 35 |
| 12 | 23 |
| 13 | 15 |
| 14 | 9 |
| 15 | 5 |
| 16 | 66 |
| 17 | 47 |
| 18 | 31 |
| 19 | 19 |
| 20 | 11 |
| 21 | 6 |
| 22 | 105 |
| 23 | 75 |
| 24 | 53 |
| 25 | 35 |
| 26 | 23 |
| 27 | 13 |
| 28 | 7 |
| 29 | 176 |
| 30 | 131 |
| 31 | 93 |
| 32 | 66 |
| 33 | 42 |
| 34 | 27 |
| 35 | 15 |
| 36 | 8 |
| 37 | 270 |
| 38 | 203 |
| 39 | 151 |
| 40 | 106 |
| 41 | 74 |
| 42 | 49 |
| 43 | 31 |
| 44 | 17 |
| 45 | 9 |
| 46 | 420 |
| 47 | 323 |
| 48 | 241 |
| 49 | 178 |
| 50 | 126 |
| 51 | 86 |
| 52 | 56 |
| 53 | 35 |
| 54 | 19 |
| 55 | 10 |
| 56 | 616 |
| 57 | 477 |
| 58 | 365 |
| 59 | 272 |
| 60 | 200 |
| 61 | 140 |
| 62 | 98 |
| 63 | 63 |
| 64 | 39 |
| 65 | 21 |
| 66 | 11 |
[1,4,2,9,5,3,20,13,7,4,35,23,15,9,5,66,47,31,19, 11,6,105,75,53,35,23,13,7,176,131,93,66,42,27,15, 8,270,203,151,106,74,49,31,17,9,420,323,241,178, 126,86,56,35,19,10,616,477,365,272,200,140,98,63, 39,21,11] |