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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 8 |
| 2 | 46 |
| 3 | 242 |
| 4 | 1234 |
| 5 | 6218 |
| 6 | 31186 |
| 7 | 156122 |
| 8 | 780994 |
| 9 | 3905738 |
| 10 | 19530226 |
| 11 | 97654202 |
| 12 | 488277154 |
| 13 | 2441398058 |
| 14 | 12207014866 |
| 15 | 61035123482 |
| 16 | 305175715714 |
| 17 | 1525878775178 |
| 18 | 7629394269106 |
| 19 | 38146972131962 |
| 20 | 190734862232674 |
[1,8,46,242,1234,6218,31186,156122,780994,3905738, 19530226,97654202,488277154,2441398058, 12207014866,61035123482,305175715714, 1525878775178,7629394269106,38146972131962, 190734862232674] |