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| n | a(n) |
|---|---|
| 1 | 8 |
| 2 | 21 |
| 3 | 80 |
| 4 | 318 |
| 5 | 1315 |
| 6 | 5364 |
| 7 | 21680 |
| 8 | 87452 |
| 9 | 352931 |
| 10 | 1425261 |
| 11 | 5757064 |
| 12 | 23253889 |
| 13 | 93921193 |
| 14 | 379334811 |
| 15 | 1532086339 |
| 16 | 6187939435 |
| 17 | 24992490166 |
| 18 | 100942222266 |
| 19 | 407695589939 |
| 20 | 1646641727295 |
| 21 | 6650621491464 |
| 22 | 26861196902537 |
| 23 | 108489696252447 |
[8,21,80,318,1315,5364,21680,87452,352931,1425261, 5757064,23253889,93921193,379334811,1532086339, 6187939435,24992490166,100942222266,407695589939, 1646641727295,6650621491464,26861196902537, 108489696252447] |