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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 10 |
| 5 | 20 |
| 6 | 58 |
| 7 | 139 |
| 8 | 438 |
| 9 | 1140 |
| 10 | 3258 |
| 11 | 9772 |
| 12 | 28562 |
| 13 | 85882 |
| 14 | 251866 |
| 15 | 805191 |
| 16 | 2408942 |
| 17 | 7397564 |
| 18 | 23342986 |
| 19 | 72959148 |
| 20 | 230591190 |
| 21 | 716489490 |
| 22 | 2346086618 |
| 23 | 7379407456 |
| 24 | 23549213138 |
| 25 | 76289251170 |
| 26 | 246337916414 |
| 27 | 799728360510 |
| 28 | 2563657338846 |
| 29 | 8524590676290 |
| 30 | 27557309877842 |
| 31 | 89945529675023 |
| 32 | 296436681030158 |
[1,1,2,3,10,20,58,139,438,1140,3258,9772,28562, 85882,251866,805191,2408942,7397564,23342986, 72959148,230591190,716489490,2346086618, 7379407456,23549213138,76289251170,246337916414, 799728360510,2563657338846,8524590676290, 27557309877842,89945529675023,296436681030158] |