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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 3 |
| 7 | 4 |
| 8 | 8 |
| 9 | 10 |
| 10 | 31 |
| 11 | 40 |
| 12 | 92 |
| 13 | 175 |
| 14 | 322 |
| 15 | 780 |
| 16 | 1450 |
| 17 | 2980 |
| 18 | 6347 |
| 19 | 14316 |
| 20 | 26603 |
| 21 | 68564 |
| 22 | 134571 |
| 23 | 305769 |
| 24 | 652196 |
| 25 | 1540518 |
| 26 | 3319397 |
| 27 | 7501500 |
| 28 | 17310417 |
| 29 | 39314522 |
| 30 | 88859173 |
| 31 | 206048559 |
| 32 | 471148762 |
| 33 | 1101002080 |
| 34 | 2593106378 |
| 35 | 5897494914 |
| 36 | 14160226476 |
| 37 | 32800988233 |
| 38 | 78429768493 |
| 39 | 183491859507 |
| 40 | 439636793429 |
[1,0,1,1,1,3,4,8,10,31,40,92,175,322,780,1450, 2980,6347,14316,26603,68564,134571,305769,652196, 1540518,3319397,7501500,17310417,39314522, 88859173,206048559,471148762,1101002080, 2593106378,5897494914,14160226476,32800988233, 78429768493,183491859507,439636793429] |