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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 14 |
| 5 | 36 |
| 6 | 90 |
| 7 | 213 |
| 8 | 520 |
| 9 | 1271 |
| 10 | 3082 |
| 11 | 7493 |
| 12 | 18238 |
| 13 | 44324 |
| 14 | 107782 |
| 15 | 262142 |
| 16 | 637368 |
| 17 | 1549870 |
| 18 | 3768886 |
| 19 | 9164499 |
| 20 | 22285034 |
| 21 | 54190024 |
| 22 | 131771616 |
| 23 | 320424614 |
| 24 | 779166270 |
| 25 | 1894671121 |
| 26 | 4607207304 |
| 27 | 11203190618 |
| 28 | 27242414612 |
| 29 | 66244451632 |
| 30 | 161084380040 |
| 31 | 391703392954 |
[1,1,2,7,14,36,90,213,520,1271,3082,7493,18238, 44324,107782,262142,637368,1549870,3768886, 9164499,22285034,54190024,131771616,320424614, 779166270,1894671121,4607207304,11203190618, 27242414612,66244451632,161084380040,391703392954] |