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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 30 |
| 4 | 128 |
| 5 | 559 |
| 6 | 2504 |
| 7 | 11446 |
| 8 | 52878 |
| 9 | 247011 |
| 10 | 1162047 |
| 11 | 5503850 |
| 12 | 26197543 |
| 13 | 125260037 |
| 14 | 601111800 |
| 15 | 2893859691 |
| 16 | 13970128793 |
| 17 | 67601744906 |
| 18 | 327818426179 |
| 19 | 1592633947709 |
| 20 | 7750307338336 |
| 21 | 37771613990443 |
| 22 | 184328164993382 |
| 23 | 900619247737124 |
| 24 | 4405202828086163 |
| 25 | 21568681136645873 |
| 26 | 105700540673190686 |
[1,2,8,30,128,559,2504,11446,52878,247011,1162047, 5503850,26197543,125260037,601111800,2893859691, 13970128793,67601744906,327818426179, 1592633947709,7750307338336,37771613990443, 184328164993382,900619247737124,4405202828086163, 21568681136645873,105700540673190686] |