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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 2 |
| 7 | 4 |
| 8 | 6 |
| 9 | 9 |
| 10 | 13 |
| 11 | 18 |
| 12 | 24 |
| 13 | 31 |
| 14 | 39 |
| 15 | 48 |
| 16 | 58 |
| 17 | 70 |
| 18 | 83 |
| 19 | 98 |
| 20 | 114 |
| 21 | 132 |
| 22 | 152 |
| 23 | 174 |
| 24 | 198 |
| 25 | 224 |
| 26 | 252 |
| 27 | 282 |
| 28 | 314 |
| 29 | 349 |
| 30 | 386 |
| 31 | 426 |
| 32 | 468 |
| 33 | 513 |
| 34 | 561 |
| 35 | 612 |
| 36 | 666 |
| 37 | 723 |
| 38 | 783 |
| 39 | 846 |
| 40 | 912 |
| 41 | 982 |
| 42 | 1055 |
| 43 | 1132 |
| 44 | 1212 |
| 45 | 1296 |
| 46 | 1384 |
| 47 | 1476 |
| 48 | 1572 |
| 49 | 1672 |
| 50 | 1776 |
[0,0,0,0,0,1,2,4,6,9,13,18,24,31,39,48,58,70,83, 98,114,132,152,174,198,224,252,282,314,349,386, 426,468,513,561,612,666,723,783,846,912,982,1055, 1132,1212,1296,1384,1476,1572,1672,1776] |