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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2047 |
| 3 | 177148 |
| 4 | 4192255 |
| 5 | 48828126 |
| 6 | 362621956 |
| 7 | 1977326744 |
| 8 | 8585738239 |
| 9 | 31381236757 |
| 10 | 99951173922 |
| 11 | 285311670612 |
| 12 | 742649588740 |
| 13 | 1792160394038 |
| 14 | 4047587844968 |
| 15 | 8649804864648 |
| 16 | 17583591913471 |
| 17 | 34271896307634 |
| 18 | 64237391641579 |
[1,2047,177148,4192255,48828126,362621956, 1977326744,8585738239,31381236757,99951173922, 285311670612,742649588740,1792160394038, 4047587844968,8649804864648,17583591913471, 34271896307634,64237391641579] |