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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 6 |
| 5 | 12 |
| 6 | 22 |
| 7 | 44 |
| 8 | 88 |
| 9 | 136 |
| 10 | 252 |
| 11 | 504 |
| 12 | 896 |
| 13 | 1792 |
| 14 | 3392 |
| 15 | 6352 |
| 16 | 9720 |
| 17 | 19440 |
| 18 | 35664 |
| 19 | 71328 |
| 20 | 129952 |
| 21 | 247232 |
| 22 | 477664 |
| 23 | 955328 |
| 24 | 1700416 |
| 25 | 2657280 |
| 26 | 5184000 |
| 27 | 10368000 |
| 28 | 19407360 |
| 29 | 38814720 |
| 30 | 68868352 |
| 31 | 137736704 |
| 32 | 260693504 |
| 33 | 505830400 |
| 34 | 999641600 |
| 35 | 1882820608 |
| 36 | 2807196672 |
[1,1,2,4,6,12,22,44,88,136,252,504,896,1792,3392, 6352,9720,19440,35664,71328,129952,247232,477664, 955328,1700416,2657280,5184000,10368000,19407360, 38814720,68868352,137736704,260693504,505830400, 999641600,1882820608,2807196672] |