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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 3 |
| 8 | 5 |
| 9 | 5 |
| 10 | 8 |
| 11 | 10 |
| 12 | 13 |
| 13 | 16 |
| 14 | 20 |
| 15 | 23 |
| 16 | 31 |
| 17 | 36 |
| 18 | 43 |
| 19 | 52 |
| 20 | 62 |
| 21 | 72 |
| 22 | 87 |
| 23 | 102 |
| 24 | 120 |
| 25 | 139 |
| 26 | 163 |
| 27 | 188 |
| 28 | 220 |
| 29 | 254 |
| 30 | 292 |
| 31 | 338 |
| 32 | 389 |
| 33 | 444 |
| 34 | 510 |
| 35 | 581 |
| 36 | 665 |
| 37 | 758 |
| 38 | 862 |
| 39 | 978 |
| 40 | 1111 |
| 41 | 1258 |
| 42 | 1422 |
| 43 | 1608 |
| 44 | 1814 |
| 45 | 2042 |
| 46 | 2302 |
| 47 | 2588 |
| 48 | 2908 |
| 49 | 3261 |
| 50 | 3655 |
| 51 | 4093 |
| 52 | 4580 |
| 53 | 5118 |
| 54 | 5714 |
| 55 | 6374 |
[0,0,0,1,1,2,3,5,5,8,10,13,16,20,23,31,36,43,52, 62,72,87,102,120,139,163,188,220,254,292,338,389, 444,510,581,665,758,862,978,1111,1258,1422,1608, 1814,2042,2302,2588,2908,3261,3655,4093,4580,5118, 5714,6374] |