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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 18 |
| 4 | 49 |
| 5 | 529 |
| 6 | 1458 |
| 7 | 15842 |
| 8 | 43681 |
| 9 | 474721 |
| 10 | 1308962 |
| 11 | 14225778 |
| 12 | 39225169 |
| 13 | 426298609 |
| 14 | 1175446098 |
| 15 | 12774732482 |
| 16 | 35224157761 |
| 17 | 382815675841 |
| 18 | 1055549286722 |
| 19 | 11471695542738 |
| 20 | 31631254443889 |
| 21 | 343768050606289 |
| 22 | 947882084029938 |
| 23 | 10301569822645922 |
| 24 | 28404831266454241 |
[1,2,18,49,529,1458,15842,43681,474721,1308962, 14225778,39225169,426298609,1175446098, 12774732482,35224157761,382815675841, 1055549286722,11471695542738,31631254443889, 343768050606289,947882084029938,10301569822645922, 28404831266454241] |