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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 4 |
| 8 | 6 |
| 9 | 8 |
| 10 | 11 |
| 11 | 14 |
| 12 | 20 |
| 13 | 24 |
| 14 | 33 |
| 15 | 41 |
| 16 | 54 |
| 17 | 66 |
| 18 | 87 |
| 19 | 105 |
| 20 | 136 |
| 21 | 165 |
| 22 | 209 |
| 23 | 253 |
| 24 | 319 |
| 25 | 383 |
| 26 | 477 |
| 27 | 574 |
| 28 | 707 |
| 29 | 847 |
| 30 | 1038 |
| 31 | 1238 |
| 32 | 1506 |
| 33 | 1794 |
| 34 | 2166 |
| 35 | 2573 |
| 36 | 3093 |
| 37 | 3660 |
| 38 | 4377 |
| 39 | 5170 |
| 40 | 6152 |
| 41 | 7245 |
| 42 | 8590 |
| 43 | 10087 |
| 44 | 11913 |
| 45 | 13959 |
| 46 | 16423 |
| 47 | 19196 |
| 48 | 22518 |
| 49 | 26252 |
| 50 | 30700 |
| 51 | 35717 |
[0,0,1,1,2,3,4,6,8,11,14,20,24,33,41,54,66,87,105, 136,165,209,253,319,383,477,574,707,847,1038,1238, 1506,1794,2166,2573,3093,3660,4377,5170,6152,7245, 8590,10087,11913,13959,16423,19196,22518,26252, 30700,35717] |