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| n | a(n) |
|---|---|
| 1 | 255 |
| 2 | 1097 |
| 3 | 4452 |
| 4 | 19851 |
| 5 | 87889 |
| 6 | 405350 |
| 7 | 1877803 |
| 8 | 8891685 |
| 9 | 42339874 |
| 10 | 204256129 |
| 11 | 989815233 |
| 12 | 4835576474 |
| 13 | 23700386333 |
| 14 | 116758334093 |
| 15 | 576519616008 |
| 16 | 2856054677187 |
| 17 | 14171463522891 |
| 18 | 70467204359198 |
| 19 | 350790297038485 |
[255,1097,4452,19851,87889,405350,1877803,8891685, 42339874,204256129,989815233,4835576474, 23700386333,116758334093,576519616008, 2856054677187,14171463522891,70467204359198, 350790297038485] |