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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 153 |
| 5 | 1121 |
| 6 | 9373 |
| 7 | 87417 |
| 8 | 898033 |
| 9 | 10052353 |
| 10 | 121492341 |
| 11 | 1573957529 |
| 12 | 21729801481 |
| 13 | 318121178337 |
| 14 | 4917743697805 |
| 15 | 79981695655801 |
| 16 | 1364227940101857 |
| 17 | 24335561350365953 |
| 18 | 452874096174214117 |
| 19 | 8772713803852981785 |
| 20 | 176541611843378273401 |
| 21 | 3684142819311127955041 |
| 22 | 79596388271096140589949 |
[1,1,5,25,153,1121,9373,87417,898033,10052353, 121492341,1573957529,21729801481,318121178337, 4917743697805,79981695655801,1364227940101857, 24335561350365953,452874096174214117, 8772713803852981785,176541611843378273401, 3684142819311127955041,79596388271096140589949] |