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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 14 |
| 4 | 45 |
| 5 | 153 |
| 6 | 548 |
| 7 | 2019 |
| 8 | 7617 |
| 9 | 29412 |
| 10 | 115631 |
| 11 | 460957 |
| 12 | 1862485 |
| 13 | 7607179 |
| 14 | 31357468 |
| 15 | 130386179 |
| 16 | 546204674 |
| 17 | 2303103834 |
| 18 | 9770915090 |
| 19 | 41679263631 |
| 20 | 178659773792 |
| 21 | 769340135930 |
| 22 | 3326719798655 |
| 23 | 14439860987742 |
| 24 | 62900346313029 |
| 25 | 274897072613460 |
| 26 | 1205054156763758 |
| 27 | 5297624732877279 |
[1,2,5,14,45,153,548,2019,7617,29412,115631, 460957,1862485,7607179,31357468,130386179, 546204674,2303103834,9770915090,41679263631, 178659773792,769340135930,3326719798655, 14439860987742,62900346313029,274897072613460, 1205054156763758,5297624732877279] |