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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 7 |
| 4 | 31 |
| 5 | 411 |
| 6 | 3571 |
| 7 | 69581 |
| 8 | 927837 |
| 9 | 23794485 |
| 10 | 433057989 |
| 11 | 13747956267 |
| 12 | 319028238387 |
| 13 | 12059110543767 |
| 14 | 341371258373471 |
| 15 | 14956914818390169 |
| 16 | 500785356155724985 |
| 17 | 24937841088996528425 |
| 18 | 965337309260747987273 |
| 19 | 53822060004016654090607 |
| 20 | 2367108984768411034367975 |
| 21 | 146026942863362312725861811 |
| 22 | 7196976785684064477225272171 |
| 23 | 486563915009872154819986680357 |
[1,1,7,31,411,3571,69581,927837,23794485, 433057989,13747956267,319028238387,12059110543767, 341371258373471,14956914818390169, 500785356155724985,24937841088996528425, 965337309260747987273,53822060004016654090607, 2367108984768411034367975, 146026942863362312725861811, 7196976785684064477225272171, 486563915009872154819986680357] |