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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 0 |
| 6 | 1 |
| 7 | 2 |
| 8 | 2 |
| 9 | 3 |
| 10 | 2 |
| 11 | 4 |
| 12 | 5 |
| 13 | 7 |
| 14 | 8 |
| 15 | 9 |
| 16 | 11 |
| 17 | 13 |
| 18 | 16 |
| 19 | 20 |
| 20 | 23 |
| 21 | 27 |
| 22 | 31 |
| 23 | 37 |
| 24 | 43 |
| 25 | 52 |
| 26 | 59 |
| 27 | 70 |
| 28 | 80 |
| 29 | 93 |
| 30 | 108 |
| 31 | 126 |
| 32 | 144 |
| 33 | 167 |
| 34 | 191 |
| 35 | 221 |
| 36 | 253 |
| 37 | 292 |
| 38 | 332 |
| 39 | 382 |
| 40 | 435 |
| 41 | 498 |
| 42 | 567 |
| 43 | 649 |
| 44 | 736 |
| 45 | 839 |
| 46 | 951 |
| 47 | 1082 |
| 48 | 1226 |
| 49 | 1393 |
| 50 | 1573 |
| 51 | 1784 |
| 52 | 2013 |
| 53 | 2277 |
| 54 | 2568 |
| 55 | 2902 |
| 56 | 3266 |
| 57 | 3683 |
| 58 | 4141 |
[0,0,0,0,0,1,2,2,3,2,4,5,7,8,9,11,13,16,20,23,27, 31,37,43,52,59,70,80,93,108,126,144,167,191,221, 253,292,332,382,435,498,567,649,736,839,951,1082, 1226,1393,1573,1784,2013,2277,2568,2902,3266,3683, 4141] |