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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 11 |
| 3 | 52 |
| 4 | 269 |
| 5 | 1414 |
| 6 | 7575 |
| 7 | 41064 |
| 8 | 224665 |
| 9 | 1237898 |
| 10 | 6859555 |
| 11 | 38187164 |
| 12 | 213408805 |
| 13 | 1196524814 |
| 14 | 6727323439 |
| 15 | 37915058384 |
| 16 | 214140178225 |
| 17 | 1211694546194 |
| 18 | 6867622511675 |
| 19 | 38981807403268 |
| 20 | 221562006394173 |
| 21 | 1260814207833750 |
| 22 | 7182599953332423 |
| 23 | 40958645048598840 |
| 24 | 233779564099963081 |
[1,2,11,52,269,1414,7575,41064,224665,1237898, 6859555,38187164,213408805,1196524814,6727323439, 37915058384,214140178225,1211694546194, 6867622511675,38981807403268,221562006394173, 1260814207833750,7182599953332423, 40958645048598840,233779564099963081] |