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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 1 |
| 3 | 0 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 4 |
| 8 | 10 |
| 9 | 18 |
| 10 | 46 |
| 11 | 95 |
| 12 | 231 |
| 13 | 524 |
| 14 | 1287 |
| 15 | 3095 |
| 16 | 7713 |
| 17 | 19125 |
| 18 | 48258 |
| 19 | 122026 |
| 20 | 311935 |
| 21 | 801061 |
| 22 | 2072629 |
| 23 | 5387753 |
| 24 | 14081981 |
| 25 | 36959506 |
| 26 | 97419796 |
| 27 | 257724555 |
| 28 | 684254908 |
| 29 | 1822560590 |
| 30 | 4869517848 |
| 31 | 13047469920 |
| 32 | 35053803135 |
[0,0,1,0,1,1,3,4,10,18,46,95,231,524,1287,3095, 7713,19125,48258,122026,311935,801061,2072629, 5387753,14081981,36959506,97419796,257724555, 684254908,1822560590,4869517848,13047469920, 35053803135] |