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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 20 |
| 6 | 42 |
| 7 | 84 |
| 8 | 204 |
| 9 | 476 |
| 10 | 798 |
| 11 | 1596 |
| 12 | 3828 |
| 13 | 7656 |
| 14 | 12276 |
| 15 | 24180 |
| 16 | 36660 |
| 17 | 73320 |
| 18 | 120840 |
| 19 | 241680 |
| 20 | 389424 |
| 21 | 785680 |
| 22 | 1294440 |
| 23 | 2588880 |
| 24 | 3848880 |
| 25 | 7147920 |
| 26 | 11264760 |
| 27 | 15926040 |
| 28 | 26057304 |
| 29 | 52114608 |
| 30 | 74421648 |
| 31 | 148843296 |
| 32 | 187159392 |
| 33 | 340949280 |
| 34 | 527531760 |
| 35 | 926505360 |
[1,1,2,4,10,20,42,84,204,476,798,1596,3828,7656, 12276,24180,36660,73320,120840,241680,389424, 785680,1294440,2588880,3848880,7147920,11264760, 15926040,26057304,52114608,74421648,148843296, 187159392,340949280,527531760,926505360] |