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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 3 |
| 8 | 4 |
| 9 | 5 |
| 10 | 7 |
| 11 | 8 |
| 12 | 13 |
| 13 | 15 |
| 14 | 20 |
| 15 | 25 |
| 16 | 31 |
| 17 | 36 |
| 18 | 45 |
| 19 | 51 |
| 20 | 65 |
| 21 | 74 |
| 22 | 89 |
| 23 | 103 |
| 24 | 121 |
| 25 | 136 |
| 26 | 159 |
| 27 | 177 |
| 28 | 208 |
| 29 | 231 |
| 30 | 265 |
| 31 | 296 |
| 32 | 335 |
| 33 | 369 |
| 34 | 416 |
| 35 | 455 |
| 36 | 514 |
| 37 | 561 |
| 38 | 625 |
| 39 | 684 |
| 40 | 756 |
| 41 | 820 |
| 42 | 904 |
| 43 | 976 |
| 44 | 1076 |
| 45 | 1160 |
| 46 | 1268 |
| 47 | 1368 |
| 48 | 1488 |
| 49 | 1596 |
| 50 | 1732 |
| 51 | 1852 |
| 52 | 2009 |
| 53 | 2145 |
| 54 | 2314 |
| 55 | 2471 |
[0,0,0,0,1,1,2,3,4,5,7,8,13,15,20,25,31,36,45,51, 65,74,89,103,121,136,159,177,208,231,265,296,335, 369,416,455,514,561,625,684,756,820,904,976,1076, 1160,1268,1368,1488,1596,1732,1852,2009,2145,2314, 2471] |