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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 9 |
| 3 | 33 |
| 4 | 155 |
| 5 | 652 |
| 6 | 3113 |
| 7 | 13874 |
| 8 | 66837 |
| 9 | 307272 |
| 10 | 1488777 |
| 11 | 6975715 |
| 12 | 33934993 |
| 13 | 161025010 |
| 14 | 785710159 |
| 15 | 3761589709 |
| 16 | 18397686843 |
| 17 | 88656750924 |
| 18 | 434438606787 |
| 19 | 2103945744667 |
| 20 | 10326023778843 |
| 21 | 50202224491800 |
| 22 | 246715654083731 |
| 23 | 1203177588869660 |
| 24 | 5919654714954755 |
| 25 | 28941493241781162 |
| 26 | 142533052461358635 |
[1,2,9,33,155,652,3113,13874,66837,307272,1488777, 6975715,33934993,161025010,785710159,3761589709, 18397686843,88656750924,434438606787, 2103945744667,10326023778843,50202224491800, 246715654083731,1203177588869660,5919654714954755, 28941493241781162,142533052461358635] |