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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 2 |
| 7 | 2 |
| 8 | 3 |
| 9 | 5 |
| 10 | 9 |
| 11 | 14 |
| 12 | 28 |
| 13 | 49 |
| 14 | 95 |
| 15 | 182 |
| 16 | 369 |
| 17 | 733 |
| 18 | 1509 |
| 19 | 3103 |
| 20 | 6504 |
| 21 | 13627 |
| 22 | 28949 |
| 23 | 61701 |
| 24 | 132457 |
| 25 | 285454 |
| 26 | 618863 |
| 27 | 1346022 |
| 28 | 2940287 |
| 29 | 6444364 |
| 30 | 14172744 |
| 31 | 31257883 |
| 32 | 69142445 |
| 33 | 153333476 |
| 34 | 340880766 |
| 35 | 759549740 |
| 36 | 1696122213 |
| 37 | 3795178540 |
| 38 | 8508326129 |
| 39 | 19109193805 |
| 40 | 42991993545 |
| 41 | 96881110654 |
[1,0,0,1,1,1,2,2,3,5,9,14,28,49,95,182,369,733, 1509,3103,6504,13627,28949,61701,132457,285454, 618863,1346022,2940287,6444364,14172744,31257883, 69142445,153333476,340880766,759549740,1696122213, 3795178540,8508326129,19109193805,42991993545, 96881110654] |