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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 8 |
| 7 | 17 |
| 8 | 38 |
| 9 | 87 |
| 10 | 203 |
| 11 | 482 |
| 12 | 1160 |
| 13 | 2822 |
| 14 | 6929 |
| 15 | 17149 |
| 16 | 42736 |
| 17 | 107144 |
| 18 | 270060 |
| 19 | 683940 |
| 20 | 1739511 |
| 21 | 4441255 |
| 22 | 11378814 |
| 23 | 29245927 |
| 24 | 75386341 |
| 25 | 194838673 |
| 26 | 504802508 |
| 27 | 1310843123 |
| 28 | 3411070838 |
| 29 | 8893590454 |
| 30 | 23230151872 |
| 31 | 60780378423 |
| 32 | 159281034709 |
[1,1,1,2,4,8,17,38,87,203,482,1160,2822,6929, 17149,42736,107144,270060,683940,1739511,4441255, 11378814,29245927,75386341,194838673,504802508, 1310843123,3411070838,8893590454,23230151872, 60780378423,159281034709] |