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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 18 |
| 5 | 51 |
| 6 | 134 |
| 7 | 328 |
| 8 | 758 |
| 9 | 1677 |
| 10 | 3594 |
| 11 | 7530 |
| 12 | 15530 |
| 13 | 31687 |
| 14 | 64190 |
| 15 | 129420 |
| 16 | 260142 |
| 17 | 521889 |
| 18 | 1045730 |
| 19 | 2093806 |
| 20 | 4190402 |
| 21 | 8384091 |
| 22 | 16772022 |
| 23 | 33548496 |
| 24 | 67102118 |
| 25 | 134210101 |
| 26 | 268426874 |
| 27 | 536861298 |
| 28 | 1073731098 |
| 29 | 2147471727 |
| 30 | 4294954094 |
| 31 | 8589920020 |
| 32 | 17179853150 |
[1,2,6,18,51,134,328,758,1677,3594,7530,15530, 31687,64190,129420,260142,521889,1045730,2093806, 4190402,8384091,16772022,33548496,67102118, 134210101,268426874,536861298,1073731098, 2147471727,4294954094,8589920020,17179853150] |