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| n | a(n) |
|---|---|
| 8 | 4 |
| 9 | 22 |
| 10 | 116 |
| 11 | 482 |
| 12 | 1966 |
| 13 | 7682 |
| 14 | 29845 |
| 15 | 115438 |
| 16 | 449870 |
| 17 | 1770788 |
| 18 | 7073065 |
| 19 | 28727652 |
| 20 | 118907910 |
| 21 | 502249944 |
| 22 | 2167410896 |
| 23 | 9563204836 |
| 24 | 43166853057 |
| 25 | 199391604156 |
| 26 | 942578850020 |
| 27 | 4559743209208 |
| 28 | 22566589645408 |
| 29 | 114215149597312 |
| 30 | 590875202641724 |
| 31 | 3122678708581528 |
[4,22,116,482,1966,7682,29845,115438,449870, 1770788,7073065,28727652,118907910,502249944, 2167410896,9563204836,43166853057,199391604156, 942578850020,4559743209208,22566589645408, 114215149597312,590875202641724,3122678708581528] |